Thanks for posting your question in the Microsoft Q&A forum.
To reactivate, sign in to the Azure portal, navigate to "Subscriptions," choose the canceled subscription, and select "Reactivate." If your subscription was disabled due to exhausting the $100 credit within the 12-month period, you can upgrade to a pay-as-you-go subscription. This allows continued use of Azure services while still retaining access to free services for the remaining 12 months from your sign-up date.
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