Can’t open billing ticket - unexpected charge after switching from Azure for Students

Hello,

I’m having a billing issue with my Azure subscription and I’m unable to open a billing support ticket through the portal, since the system doesn’t allow it without a closed invoice (I currently only have a pending charge).

What happened: I was using the “Azure for Students” plan, which provides free credits. At some point, I switched my subscription to a developer plan, without understanding that this meant I would start being charged for usage that was previously covered by the student program’s free credit. I never intended to sign up for a paid plan. As a result, I now have a pending charge of approximately R$1,400 (Brazilian reais), an amount I cannot afford and that does not reflect any intentional or conscious use of paid resources.

What I’ve already tried:

•	Opening a new support ticket through the portal (blocked due to no closed invoice yet)

•	Contacting support via live chat

•	Contacting Azure Support on Twitter/X (@AzureSupport), who told me to open a ticket, but I can’t due to the issue above

I would appreciate help with:

1.	Opening a billing ticket even without a closed invoice, or an alternative way to do so;

2.	Requesting a review/refund of the charge, since this was a configuration misunderstanding, not intentional use of a paid service;

3.	If possible, reverting my subscription back to Azure for Students.

Could someone from the Microsoft team, or anyone who has dealt with a similar situation, advise me on how to proceed? Thank you in advance for any help.