How do I dispute a charge for what seems to be a game from my iphone?

I see a description on my bank account for a charge. My wife states it is for a game that is one my phone. I have purchsed from this gamer before but I havent in the past few days and dont see where i got anything in game for a purchase of that price. Any help would be appreciated. Looks like it went through my PayPal app thru to Apple. I dont know if one of my kids did it or it somehow just charged me but I have not paid to play in this game in over a month.