Over Charges

Whenever I spend money on Fishdom , or Travel Town, or really any game that has in game purchases I get over charged. I just bought a pack of gems on travel town for $5. And $10 was taken out. The other day I bought a $2 pack on Fishdom and $6 was taken out. This has honestly been happening for a while and it makes me not trust that Apple is being legit with these charges and taking more than suppose to. It’s not right.