Unfamiliar charge from My another account for apple.com/bill

Hi Three times unfamiliar amount is getting charged from my different account and my statements shows that your account debited with amount on apple.com/bill.

Please help as i have never linked that account anywhere neither on itunes or no where else don't know why it is getting charged from my account on the name of apple.com/bill.

My account has already got debited with a total amount of rs. 6000 Please help.