Hi Raine
Thanks for posting this query.
I'm Ankush and I'll attempt my best to help you out.
Please verify with following steps,
- check the format of your phone number and country code
- try a different contact number
- switch browser (use the edge browser) or clear the browser caches
- try using incognito mode
- you may check for browser updates
- Try creating account through phone if not tried earlier
- You may try to change your mobile carrier.
- Enable- disable airplane mode and then try to validate the number.
Contact Microsoft support if above steps yield no results - https://support.microsoft.com/
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