diff --git a/src/controllers/api/accounts.ts b/src/controllers/api/accounts.ts
index e72854dc..27cf7590 100644
--- a/src/controllers/api/accounts.ts
+++ b/src/controllers/api/accounts.ts
@@ -258,7 +258,7 @@ const accountStatusesController: AppController = async (c) => {
 };
 
 const updateCredentialsSchema = z.object({
-  display_name: z.string().optional(),
+  display_name: z.coerce.string().optional(),
   note: z.coerce.string().optional(),
   avatar: fileSchema.or(z.literal('')).optional(),
   header: fileSchema.or(z.literal('')).optional(),