Obviously nobody on here can potentially refund you. Have you checked your iTunes account's purchase history (and family members accounts if you are a family organiser in family sharing) : See your purchase history in the iTunes Store on a Mac or PC - Apple Support ?
If it shows there but you didn't buy it, and if nobody else has access to the account and did it, change the account's password if you haven't already done so (What to do after you change your Apple ID email address or password - Apple Support) and contact iTunes Support : http://reportaproblem.apple.com or https://www.apple.com/emea/support/itunes/contact.html
If it doesn’t show on your account(s) (and if it isn’t : About payment card authorization holds in the iTunes Store - Apple Support) contact the card issuer