Hello George Abreu Jr,
Thank you for posting your query in the Microsoft Q&A Community.
I understand that you are not able to access the Azure portal with your user account.
From the error posted above, it shows your account doesnt exist in the tenant where you are trying to sign in to.
Something to check is if your account is a dual account and you are trying to authenticate with the wrong one. To check this, use an Incognito or InPrivate browser and see if your account is dual. Please note that this only apply or work account.
Another way to do this is to try forcing the authenticate by typing in portal.azure.com/the-tenant-id you are trying to authenticate to and see if you get the same error.
Let me know if this helps.
Babafemi