Hello Giga Goriashvili, Microsoft's policies for phone number support in account registration and security verification may vary by country or region. Some countries may have limited or restricted support for adding phone numbers to Microsoft accounts due to regional regulations, telecommunications agreements, or other factors. As an extension to the above, Microsoft does not automatically support telephony verification (including SMS) for certain region codes. See reference - https://learn.microsoft.com/en-us/entra/identity/authentication/concept-mfa-regional-opt-in. If that doesn't solve, then, you need to contact Microsoft support via one of the contacts mentioned here (you can pick location based contact) https://support.microsoft.com/en-us/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2
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