Additional sign-in or account-related issues within Microsoft Teams Free
Hi AmblyoMoron,
It is an unusual scenario. The empty field in the Azure profile is not an issue.
To confirm that your account is associated with an organization, please go to https://myapps.microsoft.com, now, click on the "Organization" icon beside "?" icon at the top right corner and confirm that you don't see the guest organization.
Also, try with another email address if you won it and check what organization set on your other email address(incorrect one).
Regards
Nik