" you're not set up to use this calling feature"

Dear Bosco,

The callback options are not offered upfront. You need to submit the request first, and the contact preference, including phone callback, is presented as part of that process. Full details are here: Get support - Microsoft 365 admin

When you raise it, describe the impact clearly and select the highest applicable severity, as a calling outage affecting multiple users should be treated as business critical rather than a general query. That has more effect on response time than the channel itself.

It is also worth confirming your role allows ticket submission, as that can affect the options you are shown. The least privileged role for this is Service Support Administrator, though several others can also submit, including Teams Administrator, Teams Communications Administrator, Helpdesk Administrator and User Administrator. If you do not hold one of these, please ask a colleague who does to raise the case on your behalf. The full list is here: Least privileged roles by task

I hope this information is helpful and provides you with a clear path forward. Should you have any further questions or need additional assistance, please don't hesitate to reach out. I'm always happy to help.

If the answer is helpful, please click "Yes" and kindly upvote it. If you have extra questions about this answer, please click "Comment".  

Note: Please follow the steps in the forum documentation to enable e-mail notifications if you want to receive the related email notification for this thread.