diff --git a/aio/content/examples/form-validation/src/app/shared/alter-ego.directive.ts b/aio/content/examples/form-validation/src/app/shared/alter-ego.directive.ts
index 6a03999dff1..44cffb280bc 100644
--- a/aio/content/examples/form-validation/src/app/shared/alter-ego.directive.ts
+++ b/aio/content/examples/form-validation/src/app/shared/alter-ego.directive.ts
@@ -42,7 +42,7 @@ export class UniqueAlterEgoValidatorDirective implements AsyncValidator {
   validate(
     control: AbstractControl
   ): Observable<ValidationErrors | null> {
-    this.validator.validate(control);
+    return this.validator.validate(control);
   }
 }
 // #enddocregion async-validator-directive