fix

app/Http/Controllers/Admin/PlanController.php

@@ -31,7 +31,7 @@ class PlanController extends Controller
             DB::beginTransaction();
             if (!User::where('plan_id', $plan->id)
                 ->get()
-                ->update(['group_id', $plan->group_id])
+                ->update(['group_id' => $plan->group_id])
             ) {
                 DB::rollBack();
                 abort(500, '保存失败');