Hi ch pavan
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
Go to the azure portal
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/cancel-azure-subscription
Navigate to the Cost Management + Billing and then select Subscriptions.
Pick the subscription you want to cancel from the list.
Click on "Cancel Subscription" at the top of the subscription page.
Follow the steps on the screen to finish canceling. You’ll get a notification once it’s canceled, and it may take up to 10 minutes to update.
If you're having trouble canceling or need more help, reach out to Microsoft Support through the Azure portal to create support request.
https://learn.microsoft.com/en-us/azure/azure-portal/supportability/how-to-create-azure-support-request
FYI: https://azure.microsoft.com/en-us/support/plans/
If you have any further queries, do let us know.
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