diff --git a/src/Squidex/app/shared/services/schemas.service.ts b/src/Squidex/app/shared/services/schemas.service.ts
index 730dccd5f..7852b6e8b 100644
--- a/src/Squidex/app/shared/services/schemas.service.ts
+++ b/src/Squidex/app/shared/services/schemas.service.ts
@@ -426,7 +426,7 @@ export class NumberFieldPropertiesDto extends FieldPropertiesDto {
         }
 
         if (this.allowedValues && this.allowedValues.length > 0) {
-            validators.push(ValidatorsEx.validValues(this.allowedValues));
+            validators.push(ValidatorsEx.validValues(this.allowedValues.map(String)));
         }
 
         return validators;