code: public function delete($server_filename)
      {
          $upload_path = config('dropzoner.upload-path');
  
          $full_path = $upload_path . $server_filename;
  
          if (\File::exists($full_path)) {
              \File::delete($full_path);
          }
  
          event(new ImageWasDeleted($server_filename));
  
          return response()->json([
              'error' => false,
              'code'  => 200
          ], 200);
      }
docs: Delete Single Image
  
  @param $server_filename
  @return mixed