Hi Watt Song
When your subscription is canceled, Microsoft waits 30 to 90 days before permanently deleting your data in case you need to access it or recover your data. We don't charge you for retaining the data. For more information, see Microsoft Trust Center - How we manage your data.
Once the subscription is reactivated, you should be able to delete the resource group as needed.
Please follow the below steps to raise a Microsoft support ticket and 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.
Please let me know if you face any challenge here, I can help you to resolve this issue further
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