Poor service

I m using Mr price account then I brought a Chino trouser only to found that the item was not fitting me I misplaced the slip.when I went in store they called the manager the manager at first she refused to talk to me over the phone after 10 to 15 minutes she answered me I was speaking Zulu as her name was Karabo she acted as if she doesn't understand Zulu.and she refused to help me without a slip, I then escalated this matter to their customer service, they also said as soon as I get the slip I must exchange the item.how am I going to get the slip as I need that trouser I don't have it.when I went to buy it it's shows that I need it meaning I'm stuck within the trouser as I can't find the slip.the service I received both in store and customer service was not good as their regular customer I'm not satisfied at all.ineed solutions mistakes happen.