"Looks like your organization isn't supported on this version of Teams."
Do you have any idea what is causing this message?
To my knowledge, there are certain types of organizations aren't eligible for Microsoft Teams free.
If you're signed in to a Microsoft 365 work or school account, you won't be able to sign up for Teams free.
Accounts at schools or other academic institutions aren't eligible for this Teams free offer.
Account at U.S. government institutions aren't eligible for this Teams free offer.
For more details about it, please refer to:
Indeed, it is possible that someone activated Office 365 with your domain.
In my experience, you can add or remove domains if you are a Global Administrator of a business or enterprise plan. If someone add your company domain in Office 365, you need to contact the administrator to remove it.
For more details about how to add and remove domains in Office 365, please refer to:
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