Unknown transactions

Hello, I’m writing you about 3 last transactions from my debit visa card, number 479049****9002, 3 times you withdraw my money (every amount is $6.99) without my permission. I already checked my subscribes and I didn’t find any app, which price is $6.99. So can you refund my money, check incomes from my card to your account and refund them? Total amount is $20.97. And please please check and solve this issue, because today you (I mean itunes) twice tried withdrawing my money. It’s annoying seriously guys. Hope for your understanding! Have a nice day!!