diff --git a/src/server/api/me/totp.post.ts b/src/server/api/me/totp.post.ts
index 53c87f8a..f3782828 100644
--- a/src/server/api/me/totp.post.ts
+++ b/src/server/api/me/totp.post.ts
@@ -23,6 +23,13 @@ export default definePermissionEventHandler(
     checkPermissions(user);
 
     if (body.type === 'setup') {
+      if (user.totpVerified) {
+        throw createError({
+          statusCode: 409,
+          statusMessage: 'TOTP is already enabled',
+        });
+      }
+
       const key = new Secret({ size: 20 });
 
       const totp = new TOTP({
@@ -50,6 +57,13 @@ export default definePermissionEventHandler(
         type: 'created',
       } as Response;
     } else if (body.type === 'delete') {
+      if (!user.totpVerified) {
+        throw createError({
+          statusCode: 409,
+          statusMessage: 'TOTP is not enabled',
+        });
+      }
+
       await Database.users.deleteTotpKey(user.id, body.currentPassword);
 
       return {
diff --git a/src/server/database/repositories/user/service.ts b/src/server/database/repositories/user/service.ts
index e3526315..b84ed365 100644
--- a/src/server/database/repositories/user/service.ts
+++ b/src/server/database/repositories/user/service.ts
@@ -221,6 +221,10 @@ export class UserService {
         throw new Error('User not found');
       }
 
+      if (txUser.totpVerified) {
+        throw new Error('TOTP is already verified');
+      }
+
       const totpKey = txUser.totpKey;
       if (!totpKey) {
         throw new Error('TOTP key is not set');
diff --git a/src/server/database/repositories/user/types.ts b/src/server/database/repositories/user/types.ts
index bb5a7290..9a175a6a 100644
--- a/src/server/database/repositories/user/types.ts
+++ b/src/server/database/repositories/user/types.ts
@@ -18,7 +18,10 @@ const remember = z.boolean({ message: t('zod.user.remember') });
 
 const totpCode = z
   .string({ message: t('zod.user.totpCode') })
+  // min and max to improve error messages
   .min(6, t('zod.user.totpCode'))
+  .max(6, t('zod.user.totpCode'))
+  .regex(/^\d{6}$/, t('zod.user.totpCode'))
   .pipe(safeStringRefine);
 
 export const UserLoginSchema = z.object({