Hi @rhl ,
Could you find the UCWA Directory in the internal web site from IIS?
Please make sure your external Web Service FQDN is pointed to the reverse proxy public IP address. The following picture shows the requirements about internal DNS and external DNS configuration for your reference:
Also, please check your certificate on Reverse Proxy. The certificate’s common name (the one you see the certificated issued to) should be the web services external URL.
In addition, we highly recommend you use Lync Connectivity analyzer to see if there is any error message and provide the detailed logs from it:
https://testconnectivity.microsoft.com/tests/skype
For more details about how to troubleshooting Mobility issue on Skype for Business Server, you can learn it from:
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