Wrong closed statments !!!!

Hi this place (E14 5HP) maybe is master head of control & management IT center for computerised programs for calculations transactions barclayscard statements! Recently barclayscard offers a new scheme names purchase plan . Which means for purchases over 400£ you will entitled to pay back to credit account by 24 instalments or less at zero percent interest. But there is a handling fee which would be add to your purchase to pay back by instalments . But I saw very accurately these fees also deduced from account straight away!! Which means. Double deductions for fees !! And also the fees comes to your statements closed plus of your main amount of purchase to pay by another card or direct debit to your Barclays credit card , which means triple payment for fees and double payments for amount of main purchase!! I called them for this big mistake and they correct my statement by deduction of main purchase and purchase plan ( handled fees) fees . But already what is left is to refund to credit card these fees which they have promised me to refund these fees!!! So I'm alerting you to take a accurate to your account and see these big mistakes in thier calculations . Really it's very very ridiculous !!!