Hello @SargunSingh Welcome to Microsoft Q&A community forum. Happy to assist you!
Based on the information you shared, I see that you are trying to activate Azure for Student subscription using your GitHub account and being greeted with message "Institution not registered".
You need to provide a phone number and your academic organization’s email address (for example, your_name@your_school.edu) to sign up for an Azure for Students subscription.
Please refer to Azure for Students FAQ doc here: https://azure.microsoft.com/en-us/free/free-account-students-faq/ that covers common questions to understand more about the eligibility and the process to be followed.
If you need further assistance, then I suggest you create a support request over here: https://azure.microsoft.com/en-us/support/create-ticket/. The ticket enables you to work closely with the support engineers and get a quick resolution to your issue.
If you are unable to create a support request, I suggest you try the following options:
Twitter : Connect with @AzureSupport on Twitter for answers, support, and to connect with Azure experts. best place to raise a request
OR
You can call global customer service - https://support.microsoft.com/en-gb/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2 to raise a support request on your behalf to help you connect with Azure billing and subscription management support.
Hope this helps!
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