Hi @MB
To build Teams apps, you must have a work or school Microsoft 365 account. Microsoft 365 personal account can't be used.
Ensure that you have the following accounts before you start building your Teams app:
1.Microsoft 365 account with a valid subscription
If you have a Visual Studio Enterprise or Professional subscription, both programs include a free Microsoft 365 developer subscription. It's active as long as your Visual Studio subscription is active. For more information, see Microsoft 365 developer subscription.
If you don't have any Microsoft 365 tenant, you might qualify for a Microsoft 365 E5 developer subscription through the Microsoft 365 Developer Program; for details, see the FAQ. Alternatively, you can sign up for a 1-month free trial or purchase a Microsoft 365 plan.
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