Trouble Using Microsoft Authenticator on Old Smart Phone

Question

I am having an issue using the Microsoft Authenticator app on my older model smartphone. Despite having a Microsoft 360 account, I cannot access various platforms (e.g., Norton, SBA.gov, etc.) because the codes provided by the Authenticator app are not recognized and are listed as invalid.

I have reached out to Norton and Microsoft for assistance but have not received a resolution. I am seeking assistance in resolving my issue with the hope that the community can help. Thanks.

Ms. Walker