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I understand that you are encountering an issue, ensure that you’re using your university or school email address, as the free Azure for Students offer is only available to students from eligible institutions. When your $100 credit is used up or the 12-month period ends, your Azure subscription will be canceled. If you're still a student at the end of the 12 months, you can renew the Azure for Students offer.
Kindly refer the below Document:
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