Hi Ayan Mehdi
Have you referred to the following document to reactivate your subscription?
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/subscription-disabled#the-subscription-was-canceled
If the issue still persists, here is the link to raise a Microsoft support ticket Azure Billing Support they will assist you to resolve your query.
1.Go to Azure Portal -> Click on help+support -> create a support request
2. If you see Support AI Assistant as shown below, click Switch to classic experience button on right. If not, proceed to step #3
3.On left, enter subscription management in the box and click Go and select service
4.Select the subscription and You will see some suggestions to resolve your issue. If none of those apply, please see the steps below.
5.Scroll down the suggestions and you will see an option to Contact support -> create a
support request.
6.Select Subscription Management and provide the details requested.
Feel free to reach out if you have any more questions—I’m happy to help
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