Hi,
can you provide the country code and number? The screenshot is not clear so I assume it is missing the country code Check the FAQs for detailed registration over here - All you need is a phone number, a credit card or a debit card (non-prepaid), and a Microsoft account or a GitHub account. Only credit cards are accepted in Hong Kong and Brazil.
https://azure.microsoft.com/en-gb/free/free-account-faq
Hope this helps.
JS
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