diff --git a/admin/src/lib/api.ts b/admin/src/lib/api.ts
index 39b5708..ee945dc 100644
--- a/admin/src/lib/api.ts
+++ b/admin/src/lib/api.ts
@@ -24,7 +24,8 @@ async function request<T>(path: string, options?: RequestInit): Promise<T> {
     throw new ApiError(res.status, body.message || 'Error de servidor');
   }
 
-  return res.json();
+  const text = await res.text();
+  return text ? JSON.parse(text) : ({} as T);
 }
 
 export const api = {
diff --git a/backend/src/auth/email-otp.service.ts b/backend/src/auth/email-otp.service.ts
index 0d07a8a..fc9861b 100644
--- a/backend/src/auth/email-otp.service.ts
+++ b/backend/src/auth/email-otp.service.ts
@@ -46,6 +46,7 @@ export class EmailOtpService {
       create: { key: 'smtp_config', value: config as any },
       update: { value: config as any },
     });
+    return { message: 'Configuración SMTP guardada' };
   }
 
   async sendOtp(email: string): Promise<void> {