修改

app/Service/ApplyOrderService.php

@@ -1304,7 +1304,7 @@ class ApplyOrderService extends Service
 
         $model = new ReportWorking();
         $order_number = $model->where('order_number','Like','%'. $str . '%')
-            ->max('order_number');
+            ->max(DB::raw('CAST(order_number AS SIGNED)'));
 
         if(empty($order_number)){
             $number = str_pad(1,3,'0',STR_PAD_LEFT);