Hello @Hanh P
You can reach out to azure support team by following the below link reference. Please ensure to share the subscription ID and invoice ID (as you mentioned you're still being charged). Support team will be able to identify the account used to create the subscription and perhaps, assist with checking and disabling it as per your request.
If you're unable to create support request, try to reach support via global customer support as shown below.
Hope this helps!
Regards
Divya.