A Microsoft offering that enables tracking of cloud usage and expenditures for Azure and other cloud providers.
@I Ketut Diatmika Caturdianta Sorry for the delayed response!
Just adding my 2 cents here:
I see that you are trying to activate your Azure for Student subscription using your academic account and being greeted with message "You're not eligible for an Azure free account". this means you may be trying to active Azure free trial account which is not the right offer. Try this link: https://azure.microsoft.com/en-in/free/students
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.
Are you sure you're using your education's organization's email address? Please refer to the Microsoft for Students FAQ over here: https://azure.microsoft.com/en-us/free/free-account-students-faq/

If you're eligible, 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.
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