Hello @Vinh Tran Thank you for contacting us through Microsoft Q&A platform. Sorry for the delayed response and for the inconvenience caused to you!
From the tile of the post, I understand that you have been charged on your sponsorship subscription. If you have been charged while having free credit from a sponsorship, there could be several reasons for this.
You will be charged for any additional usage, if you have exceeded your free credit limit.
Go to the Azure portal and check your billing history. Make sure that the charges are legitimate and not the result of a billing error.
If you have checked the above and are still unsure why you have been charged, you can contact Microsoft support for further assistance. You can contact Microsoft support through the Azure portal or by phone.
Note that if you have been charged for usage that should have been covered by your free credit, you can contact Microsoft support to request a refund. Microsoft support will investigate the issue and issue a refund if appropriate.
Here is the link - https://docs.microsoft.com/en-us/azure/azure-portal/supportability/how-to-create-azure-support-request to create support case.
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/
Or
You can call global customer service - https://support.microsoft.com/en-gb/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2 to raise a support request on your behalf to help you connect with Azure billing and subscription management support.
Hope this helps!
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