please Check the AccessLogs to see which URLs are getting Blocked while you are using the Proxy
you can filter for your mobile IP so then You will see which requests are coming to WSA.
look for HTTP response (400,401,403,404,500,502,504) for example this is the start of one Accesslog's Line :
1659336533.043 97 1.2.3.4 TCP_MISS/402
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