update

app/Http/Controllers/Server/DeepbworkController.php

@@ -17,8 +17,10 @@ class DeepbworkController extends Controller
     public function user (Request $request) {
         $nodeId = $request->input('node_id');
         $server = Server::find($nodeId);
-        $server->last_check_at = time();
-        $server->save();
+        if ($server) {
+            $server->last_check_at = time();
+            $server->save();
+        }
         $users = User::whereIn('group_id', json_decode($server->group_id))
             ->select([
                 'id',