Charged twice. Who should be responsible??

GragonFox

I play Cooking Dash on my iPAD. I bought a coin at USD 0.99 on 23rd December using my debit card. Every purchase via my debit card, I will receive a text from the bank. But on 25th December I receive a text while I was grocery shopping that I purchased something in this game. I didn't even touch my iPAD, How can this happen??. When I checked my bank account, they charged me twice. I did purchase a coin on 23rd but I never purchased anything on the 25th. I already contacted the administration from apple regarding this matter. Please help me, who should be responsible ? Thanks.