Hi Leonard,
Regarding the issue you had with our Microsoft Authenticator app that doesn't accept the codes that you entered, we suggest that you turn off any existing apps for the mean time.
Once you have turned them off, follow these steps:
- Disassociate your Microsoft account from your Authenticator app.
- After that, log on to https://account.live.com/proofs/Manage
- Click "Set up identity verification app'.
- Add you Microsoft account again.
Let us know how it goes.