@cmi Greetings!
I understand your concern about not being able to re-enable your Azure for student subscription. As per FAQ document - https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/azurestudents-subscription-disabled#you-accidentally-canceled-your-subscription If you accidentally canceled your Azure for Students subscription, you can reactivate it by contacting Azure support. From the details you provided, I understand that you were trying to re-activate your subscription but unable to find it under subscriptions or maybe it is showing as disabled. Contacting Azure support by raising a support request should help you resolve this issue. The ticket enables you to work closely with the support engineers and get a quick resolution to your issue.
Here is the link - https://docs.microsoft.com/en-us/azure/azure-portal/supportability/how-to-create-azure-support-request to create support case.
FYI: Azure Billing and Subscription Management support is included in the Basic Support Plan without any charge.
https://azure.microsoft.com/en-us/support/plans/
Hope this helps. Let us know if you have any challenges contacting Azure support.
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