@Nguyen, Chuong Thanh Thien - Welcome to Microsoft Q&A and thanks for reaching out.
Sorry for the inconvenience this must have caused!
Microsoft Azure subscription and billing related issues are currently not supported in the Q&A forums, the supported products are listed over here : https://docs.microsoft.com/en-us/answers/products (more to be added later on).
I suggest you create a support request over here: https://azure.microsoft.com/en-us/support/create-ticket/. The ticket enables you to work closely with the support engineers and get a quick resolution to your issue.
FYI: Azure Billing and Subscription Management support is included in the Basic Support Plan without any charge. https://azure.microsoft.com/en-us/support/plans/
You can also try https://azure.microsoft.com/en-us/support/options/#support-plans and ideally the “Submit a support ticket” button will work on this page for them as a first step too.
Hope this helps. and please feel free to reach out if you have any further questions.
If the above response was helpful, please feel free to "Accept as Answer" and "Upvote" the same so it can be beneficial to the community.