It appears that you are experiencing issues with phone number verification for Microsoft Rewards, specifically due to the country code for Myanmar not being supported. As indicated in the context, Azure does not support every country or region for sign-up, and if your country does not appear in the country code list, you may not be able to sign up or receive verification codes.
Unfortunately, I cannot provide a solution to this specific issue as it falls outside the scope of the provided context. It may be best to contact Microsoft support directly for assistance with your situation regarding the rewards program and phone number verification.
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