diff --git a/db/index.ts b/db/index.ts
index 4e3eb9d..4ce044e 100644
--- a/db/index.ts
+++ b/db/index.ts
@@ -47,7 +47,10 @@ export async function createBooking({
 
   if (booking.days.some((day: string) => bookedDays.includes(day))) {
     const error = new mongoose.Error.ValidationError(booking)
-    error.addError('endDate', new mongoose.Error.ValidatorError())
+    error.addError(
+      'endDate',
+      new mongoose.Error.ValidatorError({ message: 'Schon gebucht' })
+    )
     throw error
   }