Hello somebody got into my account and changed my password as soon as I noticed it I tried to change it back but during that it bought me a pack for 74.99 € because I had my credit card stored in the shop I wanted to ask or would the payment was given back because I was in an unpleasant situation

As per the Marketplace FAQ, you need to request a refund through here: Marketplace Refund Form - Formstack

It is on this page (Marketplace FAQ - Unreal Engine) under the refund tab.

I’m sorry to hear that. I strongly suggest you run a virus scan and change your passwords for our site and all others. The recommendation from qdelpeche is accurate. Please follow those guidelines and we’ll investigate and address your situation as quickly as we can.