fix #914

src/Form.php

@@ -284,7 +284,7 @@ class Form implements Renderable
     {
         $this->repository = $repository ? Admin::repository($repository) : null;
         $this->callback = $callback;
-        $this->request = clone ($request ?: request());
+        $this->request = $request ?: request();
         $this->builder = new Builder($this);
         $this->isSoftDeletes = $repository ? $this->repository->isSoftDeletes() : false;
 

src/Form/Concerns/HasFiles.php

@@ -207,7 +207,13 @@ trait HasFiles
             }
         }
 
-        $input = Arr::only($input, [Field::FILE_DELETE_FLAG, $input['_column']]);
+        $fields = [Field::FILE_DELETE_FLAG, $input['_column']];
+
+        if (isset($relation)) {
+            $fields[] = $relation;
+        }
+
+        $input = Arr::only($input, $fields);
 
         $this->request->replace($input);