Thank you for your recent buying of our products B and C, costing HK$15.oo However, we noted that you have overpaid us $5.00 in your buying of our product A, costing $10.oo instead of $15.00. In this circumstance, you can just pay us $10.oo instead of the total cost of $15.00 in this purchase. Thanks again for your kind patronage in our products.