Azure Portal: Unable to create a billing support ticket for a refund (Infinite redirect loop)

Hello.

I am a student and I was accidentally charged for an Azure Database for PostgreSQL flexible server (Resource group: Bed4Head, Subscription ID: 90d26d7a-a852-4882-8c88-940486495aba) which I forgot to delete. I have already deleted all the resources to prevent any further charges.

I am trying to create a support ticket to request a refund, but the Azure Portal is stuck in an infinite loop. When I click "Create a support request" or "Submit a support request", it redirects me to the automated "Refund request" page which says:

"Expedited refund is supported only for subscriptions linked to an active billing profile. Submit a support request to get a refund."

However, clicking that button just closes the window or sends me back to the FAQ articles. I cannot bypass this screen to write a message to a support agent.

Could a Microsoft engineer please help me open a billing support ticket manually for my subscription? Thank you!