diff --git a/.gitea/workflows/ci.yml b/.gitea/workflows/ci.yml
index fb723ad..8581e32 100644
--- a/.gitea/workflows/ci.yml
+++ b/.gitea/workflows/ci.yml
@@ -345,6 +345,16 @@ jobs:
           E2E_BASE_URL=http://localhost:5173 \
             pnpm --filter @dorfteich/web exec playwright test e2e/social.spec.ts
 
+      - name: Reset login rate limit before admin-settings pack
+        run: |
+          echo "DELETE FROM rate_limits WHERE key LIKE 'login%';" | \
+            pnpm --filter @dorfteich/api exec prisma db execute --stdin --url "$DATABASE_URL"
+
+      - name: Run admin-settings pack
+        run: |
+          E2E_BASE_URL=http://localhost:5173 \
+            pnpm --filter @dorfteich/web exec playwright test e2e/admin-settings.spec.ts
+
       - name: Reset login rate limit before admin-quotas pack
         run: |
           echo "DELETE FROM rate_limits WHERE key LIKE 'login%';" | \
diff --git a/apps/web/e2e/admin-settings.spec.ts b/apps/web/e2e/admin-settings.spec.ts
new file mode 100644
index 0000000..2b0e2b1
--- /dev/null
+++ b/apps/web/e2e/admin-settings.spec.ts
@@ -0,0 +1,54 @@
+import { expect, test } from '@playwright/test';
+
+import { contextForUser } from './helpers';
+
+const BASE_URL = process.env.E2E_BASE_URL ?? 'http://localhost:5173';
+
+/**
+ * The general admin settings card saves THROUGH THE FORM (issue #322).
+ *
+ * This must drive the UI, not the api: the bug it fences was invisible to
+ * every api-level test — react-hook-form nested the dotted field names on
+ * input, the strict PATCH schema rejected the body, and the form looked
+ * fine while never saving. Verified end to end: success message, the value
+ * survives a full reload, the api returns it, and the TopBar picks it up
+ * without a reload (branding query invalidation).
+ */
+test('instance name changed in the general settings form persists', async ({ browser }) => {
+  const admin = await contextForUser(browser, BASE_URL, 'fixture-admin');
+  const before = (
+    (await (await admin.request.get('/api/v1/admin/settings')).json()) as Record<string, unknown>
+  )['instance.name'] as string;
+  const newName = `Renamed ${Date.now()}`;
+
+  const nameLabel = /^(Instance name|Name der Instanz)$/;
+  const page = await admin.newPage();
+  try {
+    await page.goto('/admin');
+    const generalCard = page
+      .locator('section.settings-section')
+      .filter({ has: page.getByLabel(nameLabel) });
+    await page.getByLabel(nameLabel).fill(newName);
+    await generalCard.getByRole('button', { name: /^(Save|Speichern)$/ }).click();
+    // Scoped to the card: the page has several forms with status regions.
+    await expect(generalCard.getByRole('status')).toHaveText(/^(Saved\.|Gespeichert\.)$/);
+
+    // The TopBar shows the new name without a reload — the save invalidates
+    // the branding query the TopBar reads from.
+    await expect(page.locator('.topbar__brand')).toHaveText(newName);
+
+    // The proof the form really persisted: the value survives a reload and
+    // the api returns it.
+    await page.reload();
+    await expect(page.getByLabel(nameLabel)).toHaveValue(newName);
+    const stored = (
+      (await (await admin.request.get('/api/v1/admin/settings')).json()) as Record<string, unknown>
+    )['instance.name'];
+    expect(stored).toBe(newName);
+  } finally {
+    await admin.request.patch('/api/v1/admin/settings', {
+      data: { 'instance.name': before },
+    });
+    await admin.close();
+  }
+});
diff --git a/apps/web/e2e/vs-nfd-marking.spec.ts b/apps/web/e2e/vs-nfd-marking.spec.ts
index 820947c..b676eff 100644
--- a/apps/web/e2e/vs-nfd-marking.spec.ts
+++ b/apps/web/e2e/vs-nfd-marking.spec.ts
@@ -34,7 +34,7 @@ test('mode marked: card, checkbox marking, and point-of-choice marking', async (
   // select value — compliant choice clears it, violating choice brings it
   // back, no save in between.
   const regField = page.locator('label.field', {
-    has: page.locator('select[name="auth.registrationMode"]'),
+    has: page.locator('select[name="registrationMode"]'),
   });
   const regSelect = regField.locator('select');
   await regSelect.selectOption('open');
@@ -72,7 +72,7 @@ test('mode hidden: rows disappear, notes mark the hiding, a11y clean', async ({
 
   // Value-listed control: the compliant registration mode keeps only its
   // compliant choice (seed leaves it open = violating? then all options).
-  const regSelect = page.locator('select[name="auth.registrationMode"]');
+  const regSelect = page.locator('select[name="registrationMode"]');
   const regField = page.locator('label.field', { has: regSelect });
   const optionCount = await regSelect.locator('option').count();
   const marked = await regField.locator('.vs-nfd-mark').count();
diff --git a/apps/web/src/pages/AdminSettingsPage.tsx b/apps/web/src/pages/AdminSettingsPage.tsx
index cf4091c..36957ea 100644
--- a/apps/web/src/pages/AdminSettingsPage.tsx
+++ b/apps/web/src/pages/AdminSettingsPage.tsx
@@ -5,10 +5,17 @@ import { useForm } from 'react-hook-form';
 import { useTranslation } from 'react-i18next';
 import { Link } from 'react-router-dom';
 
+import { BRANDING_KEY } from '../branding/use-branding';
 import { Field, FormError, FormSuccess } from '../components/forms';
 import { SettingsLayout } from '../components/SettingsLayout';
 import { VsNfdHiddenNote, VsNfdMark, useVsNfdMarking } from '../components/vs-nfd';
 import { apiGet, apiPatch } from '../lib/api';
+import {
+  GENERAL_FORM_FIELDS,
+  GeneralSettingsForm,
+  toFormValues,
+  toSettingsPatch,
+} from './admin-settings-form';
 import { BrandingManager } from './BrandingManager';
 import { CustomFontManager } from './CustomFontManager';
 import { PluginManager } from './PluginManager';
@@ -51,15 +58,23 @@ export function AdminSettingsPage(): React.JSX.Element {
     queryFn: () => apiGet<InstanceSettings>('/admin/settings'),
   });
 
-  const form = useForm<InstanceSettings>({ values: settings.data });
+  // Dot-free field names with an explicit mapping to the dotted settings
+  // keys — see admin-settings-form.ts for why the names must not contain
+  // dots (issue #322).
+  const form = useForm<GeneralSettingsForm>({
+    values: settings.data ? toFormValues(settings.data) : undefined,
+  });
   const vsNfd = useVsNfdMarking();
 
   const onSubmit = form.handleSubmit(async (input) => {
     setError(null);
     setSaved(false);
     try {
-      await apiPatch('/admin/settings', input);
+      await apiPatch('/admin/settings', toSettingsPatch(input));
       await queryClient.invalidateQueries({ queryKey: ['admin', 'settings'] });
+      // The TopBar takes the instance name from the public branding query;
+      // without this it keeps the old name until its staleTime runs out.
+      await queryClient.invalidateQueries({ queryKey: BRANDING_KEY });
       setSaved(true);
     } catch (err) {
       setError(err);
@@ -91,22 +106,19 @@ export function AdminSettingsPage(): React.JSX.Element {
             <FormError error={error} />
             <FormSuccess message={saved ? t('settings:admin.saved') : null} />
             <Field label={t('settings:admin.instanceName')}>
-              <input type="text" {...form.register('instance.name')} />
+              <input type="text" {...form.register('instanceName')} />
             </Field>
             <Field label={t('settings:admin.defaultLocale')}>
-              <select {...form.register('instance.defaultLocale')}>
+              <select {...form.register('defaultLocale')}>
                 <option value="de">{t('settings:profile.locales.de')}</option>
                 <option value="en">{t('settings:profile.locales.en')}</option>
               </select>
             </Field>
             <Field
               label={t('settings:admin.registrationMode')}
-              marking={vsNfd.markingFor(
-                'auth.registrationMode',
-                form.watch('auth.registrationMode'),
-              )}
+              marking={vsNfd.markingFor('auth.registrationMode', form.watch('registrationMode'))}
             >
-              <select {...form.register('auth.registrationMode')}>
+              <select {...form.register('registrationMode')}>
                 {!vsNfd.hides('auth.registrationMode', settings.data['auth.registrationMode']) && (
                   <option value="open">{t('settings:admin.registrationOpen')}</option>
                 )}
@@ -118,10 +130,10 @@ export function AdminSettingsPage(): React.JSX.Element {
               hint={t('settings:admin.newPageClassificationHelp')}
               marking={vsNfd.markingFor(
                 'classification.newPageDefault',
-                form.watch('classification.newPageDefault'),
+                form.watch('newPageClassification'),
               )}
             >
-              <select {...form.register('classification.newPageDefault')}>
+              <select {...form.register('newPageClassification')}>
                 {!vsNfd.hides(
                   'classification.newPageDefault',
                   settings.data['classification.newPageDefault'],
@@ -136,12 +148,9 @@ export function AdminSettingsPage(): React.JSX.Element {
             <Field
               label={t('settings:admin.uploadPolicy')}
               hint={t('settings:admin.uploadPolicyHelp')}
-              marking={vsNfd.markingFor(
-                'classification.uploadPolicy',
-                form.watch('classification.uploadPolicy'),
-              )}
+              marking={vsNfd.markingFor('classification.uploadPolicy', form.watch('uploadPolicy'))}
             >
-              <select {...form.register('classification.uploadPolicy')}>
+              <select {...form.register('uploadPolicy')}>
                 {!vsNfd.hides(
                   'classification.uploadPolicy',
                   settings.data['classification.uploadPolicy'],
@@ -160,15 +169,18 @@ export function AdminSettingsPage(): React.JSX.Element {
           <form onSubmit={onSubmit} noValidate>
             {(
               [
-                'quota.editorsPerPond',
-                'quota.readersPerPond',
-                'quota.additionalPonds',
-                'quota.storageBytes',
-                'quota.maxFileBytes',
+                'quotaEditorsPerPond',
+                'quotaReadersPerPond',
+                'quotaAdditionalPonds',
+                'quotaStorageBytes',
+                'quotaMaxFileBytes',
               ] as const
-            ).map((key) => (
-              <Field key={key} label={tQuotas(`defaults.${SETTING_TO_QUOTA_KEY[key]}`)}>
-                <input type="number" min={0} {...form.register(key, { valueAsNumber: true })} />
+            ).map((field) => (
+              <Field
+                key={field}
+                label={tQuotas(`defaults.${SETTING_TO_QUOTA_KEY[GENERAL_FORM_FIELDS[field]]}`)}
+              >
+                <input type="number" min={0} {...form.register(field, { valueAsNumber: true })} />
               </Field>
             ))}
             <button type="submit" className="button" disabled={form.formState.isSubmitting}>
diff --git a/apps/web/src/pages/admin-settings-form.test.ts b/apps/web/src/pages/admin-settings-form.test.ts
new file mode 100644
index 0000000..002b9a8
--- /dev/null
+++ b/apps/web/src/pages/admin-settings-form.test.ts
@@ -0,0 +1,53 @@
+import { describe, expect, it } from 'vitest';
+
+import {
+  GENERAL_FORM_FIELDS,
+  GeneralSettingsForm,
+  toFormValues,
+  toSettingsPatch,
+} from './admin-settings-form';
+
+describe('admin general settings form model (issue #322)', () => {
+  // The regression this file exists for: a dotted field name makes
+  // react-hook-form nest the typed value and the strict PATCH schema
+  // reject the body — the form then looks fine but never saves.
+  it('uses no dots in any form field name', () => {
+    for (const field of Object.keys(GENERAL_FORM_FIELDS)) {
+      expect(field).not.toContain('.');
+    }
+  });
+
+  it('round-trips settings through form values back to a flat patch', () => {
+    const settings = {
+      'instance.name': 'My Wiki',
+      'instance.defaultLocale': 'de',
+      'auth.registrationMode': 'closed',
+      'classification.newPageDefault': 'unclassified',
+      'classification.uploadPolicy': 'warn',
+      'quota.editorsPerPond': 5,
+      'quota.readersPerPond': 50,
+      'quota.additionalPonds': 0,
+      'quota.storageBytes': 1024,
+      'quota.maxFileBytes': 25,
+    };
+    expect(toSettingsPatch(toFormValues(settings))).toEqual(settings);
+  });
+
+  it('patches only the settings this form edits, under their dotted keys', () => {
+    const input: GeneralSettingsForm = {
+      instanceName: 'Renamed',
+      defaultLocale: 'en',
+      registrationMode: 'open',
+      newPageClassification: 'vs_nfd',
+      uploadPolicy: 'block',
+      quotaEditorsPerPond: 1,
+      quotaReadersPerPond: 2,
+      quotaAdditionalPonds: 3,
+      quotaStorageBytes: 4,
+      quotaMaxFileBytes: 5,
+    };
+    const patch = toSettingsPatch(input);
+    expect(patch['instance.name']).toBe('Renamed');
+    expect(Object.keys(patch).sort()).toEqual(Object.values(GENERAL_FORM_FIELDS).slice().sort());
+  });
+});
diff --git a/apps/web/src/pages/admin-settings-form.ts b/apps/web/src/pages/admin-settings-form.ts
new file mode 100644
index 0000000..1e3d2b2
--- /dev/null
+++ b/apps/web/src/pages/admin-settings-form.ts
@@ -0,0 +1,60 @@
+/**
+ * Form model of the general + quota cards on the admin settings page.
+ *
+ * Field names MUST NOT contain dots: react-hook-form treats a dot in a
+ * field name as a nested-path separator. A field registered under its
+ * settings key ('instance.name') DISPLAYS fine — RHF's getter falls back
+ * to the literal flat key — but typing writes the value into a nested
+ * object ({ instance: { name } }), which the api's strict PATCH schema
+ * rejects, so nothing ever saved (issue #322). This mapping is the single
+ * place tying a dot-free field name to its dotted settings key; the
+ * converters below translate in both directions.
+ */
+
+export const GENERAL_FORM_FIELDS = {
+  instanceName: 'instance.name',
+  defaultLocale: 'instance.defaultLocale',
+  registrationMode: 'auth.registrationMode',
+  newPageClassification: 'classification.newPageDefault',
+  uploadPolicy: 'classification.uploadPolicy',
+  quotaEditorsPerPond: 'quota.editorsPerPond',
+  quotaReadersPerPond: 'quota.readersPerPond',
+  quotaAdditionalPonds: 'quota.additionalPonds',
+  quotaStorageBytes: 'quota.storageBytes',
+  quotaMaxFileBytes: 'quota.maxFileBytes',
+} as const;
+
+export type GeneralFormField = keyof typeof GENERAL_FORM_FIELDS;
+export type GeneralFormSettingKey = (typeof GENERAL_FORM_FIELDS)[GeneralFormField];
+
+export interface GeneralSettingsForm {
+  instanceName: string;
+  defaultLocale: 'de' | 'en';
+  registrationMode: 'open' | 'closed';
+  newPageClassification: 'unclassified' | 'vs_nfd';
+  uploadPolicy: 'warn' | 'block';
+  quotaEditorsPerPond: number;
+  quotaReadersPerPond: number;
+  quotaAdditionalPonds: number;
+  quotaStorageBytes: number;
+  quotaMaxFileBytes: number;
+}
+
+/** The settings this form reads and writes, keyed by their dotted names. */
+export type GeneralFormSettings = Record<GeneralFormSettingKey, unknown>;
+
+export function toFormValues(settings: GeneralFormSettings): GeneralSettingsForm {
+  return Object.fromEntries(
+    Object.entries(GENERAL_FORM_FIELDS).map(([field, key]) => [field, settings[key]]),
+  ) as unknown as GeneralSettingsForm;
+}
+
+/** Flat dotted keys, exactly what PATCH /admin/settings expects. */
+export function toSettingsPatch(input: GeneralSettingsForm): GeneralFormSettings {
+  return Object.fromEntries(
+    Object.entries(GENERAL_FORM_FIELDS).map(([field, key]) => [
+      key,
+      input[field as GeneralFormField],
+    ]),
+  ) as GeneralFormSettings;
+}