Dear M Y V,
Thank you for posting to Microsoft Community. We are glad to assist you!
Regarding your query about Microsoft Authenticator, please understand that this query is outside our expertise as we are Microsoft 365/Exchange Online support.
Additionally, we do not have much resource/knowleage about Microsoft Authenticator, we suggest you contact Microsoft business support team: https://learn.microsoft.com/en-us/microsoft-365/admin/get-help-support?view=o365-worldwide or Contact Us - Microsoft Support
Then, you will get some particular guidance for your case.
Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution.
I hope the information helps! If there is any update or I misunderstand you, please feel free to let me know. I will continue to assist you. Your understanding and co-operation are highly appreciated.
Best Regards,
Schneider-P MSFT | Microsoft Community Support Specialist