Hi Ali Zandieh
Log in to the Azure portal
Navigate to Cost Management + Billing.
Select Subscriptions (or Azure subscriptions, depending on your view).
From the list, choose the subscription you wish to cancel.
At the top of the page, select Cancel.
If there are any resources still associated with the subscription, Azure will display them. Review and then click on Cancel subscription.
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/cancel-azure-subscription#cancel-a-subscription-in-the-azure-portal
https://learn.microsoft.com/en-us/azure/cost-management-billing/manage/cancel-azure-subscription#how-do-i-delete-my-azure-account
let us know if any help, we will always help as you needed.!
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