This error often comes down to account, app permissions or network problems. Make sure you're signed into a Microsoft account, the app is updated and it has access to things like the microphone and network. Trying a different device or switching networks can help too. If everything looks fine, it might be a temporary issue on Microsoft’s end, so checking their service status page is worth a try.
Translator not creating a session
I am trying to open a Conversation in Microsoft Translator and continually get an error message of "CANNOT CREATE A NEW CONVERSATION, PLEASE TRY AGAIN". I have a solid WiFi connection, but have tried going to my cellular network just to see if that works, and it still doesn't. All the Translation parts of the app work, EXCEPT multiple user Conversations. I've rebooted the phone, Uninstalled and Reinstalled the app, checked Bluetooth, Settings in the app, and they all look fine. This was to be used in a Parent / Teacher meeting tonight and it not working was tremendous let down. Not what I expected from Microsoft, for sure.