Bad service

I went to do an exchange at Westgate mall without a slip and I explained to them that the slip was left at Clearwater mall when I returned some items back they told they needed to keep the slip due to the items I returned. But Westgate refused to do the exchange, now my question is why did Clearwater keep the slip if they know I cannot be allowed the exchange the other items without it at another store.

As if that was not enough on exit with the goods they refused to exchange I was treated like a ***** by one of the staff because I had no slip for those items I came to exchange, she already concluded that I stole them fortunately I found the sticker that they normally give you by the door when returning items.

Such bad service from edgars Westgate mall.