app/Filament/Resources/ProductCharacteristicsMasterResource.php

@@ -444,6 +444,7 @@ class ProductCharacteristicsMasterResource extends Resource
                             })
                             ->afterStateUpdated(function ($state, callable $set, callable $get) {
                                 $set('Item', null);
+                                $set('work_group_master', null);
                                 $set('Machine', null);
                             }),
                         Select::make('Line')