Hello @Mahyar Ali Asgari
Thank you for reaching out. If the only global admin has lost their password and the other global admin is also unavailable, you may have difficulty accessing the global admin account. However, there are a few options you can try to recover or regain access to the global admin account.
- Use the Azure AD Password Reset feature: If the global admin account has been set up for Azure AD Password Reset, you can use this feature to reset the password. This requires that the admin has set up an alternate email address or phone number for password reset. For more information please review following document: Reset my admin password
- Contact Microsoft Support: If you are unable to reset the password using the above methods, you can contact Microsoft Support for assistance. They may be able to help you recover the global admin account.
I hope this answer helps to resolve your issue.
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