Hi, Jacqueline,
Remember these errors. I encountered them before.
1st line is telling you the call is not established, and the 2nd line is telling you your phone is unable to register to the GC.
If you are using a Mobile App, you need to try a different WIFI connection, it may somehow blocked. Or you will need to recreate your phone entry in GC.
In the scenario, you are using a web browser, you can use the phone diagnostics feature to check your WebRTC phone readiness.
Or, if you are not using WebRTC phone, but GC softphone, you may try to re-provision your softphone to check if it can register successfully.
Hope this is helpful to you!
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Johnson Lu
MFE International Pte Ltd.
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