@g.gravina@avanade.com Thank you for reaching out to us, As I understand you are not receiving any code / message / sms for one of the organizations where MFA is enabled. Would recommend reviewing few basic troubleshooting steps as mentioned here .
If the above-mentioned link doesn't help, try reaching out to the Global admin of the directory where your account is part of and check if they made any changes to your account - https://learn.microsoft.com/en-us/entra/identity/authentication/howto-mfa-userdevicesettings
And if you are the only Global admin of the directory in that case refer to this QnA post - https://learn.microsoft.com/en-us/answers/questions/1455267/global-admin-account-locked-unable-to-access-entra where you need to work with our data protection team by calling our customer service team, they would assist in creating a ticket for you after validating your details.
Let me know if this info helps, else happy to connect offline to discuss further on the same.