empty strings or zero will be converted to null

bizmatch/src/app/components/validated-input/validated-input.component.ts

@@ -27,8 +27,8 @@ export class ValidatedInputComponent extends BaseInputComponent {
     super(validationMessagesService);
   }
 
-  onInputChange(event: Event): void {
-    this.value = event;
-    this.onChange(event);
+  onInputChange(event: string): void {
+    this.value = event?.length > 0 ? event : null;
+    this.onChange(this.value);
   }
 }