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if you exhaust your available credits, your Azure subscription will be disabled. You may then upgrade to a Pay-As-You-Go subscription by contacting Azure Support. This allows continued use of Azure.
Azure for Students is available only to students who meet the following requirements.
- You must affirm that you are age 18 or older and attend an accredited, degree-granting two-year or four-year educational institution where you’re a full-time student in a STEM-related field.
- You must verify your academic status through your organisation’s email address. This offer is not available for use in a massive open online course (MOOC) or in other professional trainings from for-profit organizations. This offer is limited to one Azure for Students subscription per eligible customer, is non-transferable and cannot be combined with any other offer unless otherwise permitted by Microsoft. Azure for Students has a limited supply of activations and the offer is available only while supplies last. Microsoft may terminate this offer at our sole discretion. Other restrictions may apply. For more information, refer here
I would recommend to refer eligibility criteria FAQ here : https://azure.microsoft.com/en-in/free/free-account-students-faq/ If you need further support feel free to contact support team here : https://azure.microsoft.com/en-in/support/
Hope this helps.