Hi ,
Thanks for reaching out to Microsoft Q&A.
This error usually happens due to phone number formatting issues, carrier restrictions, or too many attempts. Make sure your number is in international format (example: +91XXXXXXXXXX), avoid special characters, and try a different browser or device. If the issue persists, wait 15 to30 mins before retrying or use a different phone number. If nothing works, raise a support ticket in the azure portal under "Help + Support" > "Subscription Management" > "Upgrade my Azure subscription."
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