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AADSTS50020: User account 'teerapolsri@yahoo.com' from identity provider 'live.com' does not exist in tenant 'Virtus Technology Co.,Ltd.' and cannot access the application '5e3ce6c0-2b1f-4285-8d4b-75ee78787346'(Microsoft Teams Web Client) in that tenant. The account needs to be added as an external user in the tenant first. Sign out and sign in again with a different Azure Active Directory user account.

I registered Microsoft Teams for free and do not have Azure Active Directory user account

What should I do next?

Thanks