Mistreated at ZARA MALL OF AFRICA

I went to Zara ( MALL OF AFRICA) on Saturday the 19th September for shopping. While standing in a queue to make payment one lady in front of me was complaining about a trouser she purchased and she wanted to change. The cashier said the trouser was old, I had the same challenge with the similar trouser that torn few days after I purchased is but i had lost the slip and thought they were not able to assist me. The cashier changed the same old trouser and advised me to bring back those 2 trousers i bought because its their factory fault. I went back yesterday the 22nd of September with both trousers and the manager refused to change for me the same lady who assisted that lady was there and she couldn't say anything. On my way out they started laughing at me and i felt life a fool, first of all you wasted my time advised me to bring your **** trousers that i bought for R1240 and treated me like trash and on top of that you laughed at me. I have never seen such disrespect and disgusting way of treating your clients. I have been a regular customer but after this experience i hate to shop at ZARA. I also thing they do not train their employees very unprofessional if a manager can laugh at clients what do you expect from the rest of the team hope fully am the last person to be treated this way ...