Things you can do to avoid stuff like this happening:
Not reusing the same login/password details on multiple sites.
Not reusing the same security questions on multiple sites.
Not giving every website your phone number.
Not saving your credit card details on any site.
Not having in-game purchases of intermediary currency enabled on your account.
Now go and have all of those charges reversed. You'll probably get banned of course, but hopefully you have learned a valuable lesson here.