Student premium discount didn't work and they charged me

[BloodyDavid1]

Hello
It's been 7 days since I applied to the student discount in Colombia, apparently everything went well because my university was on the list and I uploaded the documents to verify, but never got any response. What I did get was two charges on my debit card (which are the same amount of money as the standard premium upgrade). I read here that my money was supposed to be reimbursed within 3 to 5 days, but nothing has happened. No premium, no money back.
What should I do to fix this?
Thank you.