Hi @jpcapone
Could you describe when and where did you dial out in Microsoft Teams?
There are two main reasons why this error occurs. One is that you don’t have an active Office 365 Calling Plan license that supports conference calls. The other one is that your IT admin forgot to set up certain Calling Plan settings.
If Microsoft is your phone provider and you have a Phone System License from them, ensure you assigned the right phone number to the user. If a phone number has already been associated with the respective user account, remove it and assign it again.
Besides, you need to add the Emergency location. That’s a compulsory step when you set up Calling Plans. Each phone number or user needs to have an emergency location. For more information, check out Microsoft’s Support page on how to assign or change an emergency location for a user.
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