Hi Anthony LAW,
Thank you for reaching out to us on the Microsoft Q&A forum.
If you exceed your spending limit or your credit expires, your Azure membership may be disabled. In addition, it may be disabled if your credit card limit is reached, you owe money, violations of Terms of Service or the Account Administrator terminated the subscription.
You can refer the below link for more information. Hope this helps. https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/subscription-disabled
For reactivating the Azure subscription: https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/subscription-disabled?source=recommendations If you are still facing any issue in the reactivating the Azure subscription. We suggest you create a support ticket by using the below link: https://azure.microsoft.com/en-us/support/create-ticket
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