Hello
Azure Subscription and billing support ticket is free of cost that can be created.
Please use the reference document section link to create Azure Subscription and billing request: https://learn.microsoft.com/en-us/azure/azure-portal/supportability/how-to-create-azure-support-request#go-to-help--support-from-the-global-header
If you still face issue try to reach support via global customer support as shown below.
Ensure to share your preferred contact method and all the details about your query or issue and the team will connect with you.
Hope this helps!
Regards
Divya.