My experience is bad with Mr price, as a new account card holder, how can I be owing R130, 57 for purchasing only 1 per of shoes that cost only R70

My experience is bad with Mr price, as a new account card holder, how can I be owing R130, 57 for purchasing only 1 per of shoes that cost only R70. I'm not happy at its more like I'm buying 2 pers of shoes I really need an explanation on how come, I have sended an email regarding this issue but no play.