MacOS WebView Mutual TLS client certificate

I use WebView to implement some Mutual TLS client certificate authentication. I did not implement didReceiveAuthenticationChallenge or any other authentication delegate function. I just use WebView to load the auth URL with [[authWebView mainFrame] loadHTMLString:myHtml]. For some users, client cert was sent after Certificate Request from server but for other users empty certificate was sent. I am sure that there is only one valid client cert for all users. Is there anyway to make sure WebView will send find and send the client certificate after Certificate Request?
MacOS WebView Mutual TLS client certificate
 
 
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