wkwebview not loading some resource

On ios15, when loading a page, occasionally all resources under a domain name cannot be loaded. the code like this:

<html><head>
    <title>issue page</title>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no">
</style></head>

  <body><div>
    <script type="text/javascript" src="https://wx.qq.com/open/js/jweixin-1.6.0.js"></script>
    <script type="text/javascript" src="https://wap.xxxx.com/static/webapp/common_res/3rd/jquery-3.6.2.min.js"></script>
    <script type="text/javascript" src="https://statres.ok.com/quickapp/js/qa_router.min.js"></script>
    <script type="text/javascript" src="https://wap.xxxx.com/static/webapp/common_res/js/utils.min.js"></script>  
</div></html>

This is a simplified page code. The problem is that the page cannot be loaded. Resources under wx.qq.com and statres.ok.com can be loaded, but all resources under wap.xxxx.com fail to be loaded. (Debugging via safari)

wkwebview did not call back to didFinishNavigation, and the page load progress was stuck at 0.5. And then it didn't go out of time. It just stayed there.

Here are some of the solutions I tried:

1、At first I thought it was a resource problem, but everything worked fine when I copied it to safari. In addition, most of the time in my page is fine, but once this problem occurs, the page will no longer load out until I restart the app.

2、thought is to cache problem, repetition, I added NSURLRequestReloadIgnoringLocalCacheData, also was not used.

3、 I captured the system logs through idevicesyslog and found no obvious anomalies in webkit.

4、When I used wireshark to find the problem, wap.xxxx.com did not even initiate dns requests, as if the browser ignored the resource.(Normally, I caught the dns request for this page)

Please help me divergent ideas, thank you!