Authenticator: Unexpected error. Please contact your local IT administrator to resolve the problem

I created a new work account to trial Power Automate for 30 days. However, I am unable to log in because the system is prompting me to set up multi-factor authentication (MFA). When attempting to set up MFA with the Microsoft Authenticator app, I encounter an error message:

"Unexpected error. Please contact your local IT administrator to resolve the problem."

As the Global Administrator for this account, I am unable to bypass the MFA setup and cannot access the Power Automate trial or any admin settings.

Please assist as I would like to cancel the subscription.