Hello SamAzure,
Based on your query, I understand that while you’re able to access Outlook.com, you're currently unable to access the Azure portal due to an issue completing the MFA process through the Authenticator app.
Could you please confirm whether you’re seeing the number matching prompt on your mobile device when trying to sign in? Also, please let me know if you are the only Global Administrator in your tenant.
Once we have this information, we can connect offline to discuss the issue further and assist you with resolving it.