Mtn vangate mall is ****

I bought my huawei p smart in March 2018 at MTN VANGATE MALL. THE WORSE MTTN SHOP EVER. Along with the phone I bought a plastic looking screen guard for R299 and I was told by the consult, Shaun, that this screen guard is way better than the glass and I took his word for it, keeping in mind I use to buy R50 screen guards by the shops close by to me. So the other day I put phone in my jacket pocket as I always do I took out after a few seconds and this supposed fantastic screen guard rolled off my phone and I put it back on and now it looks like **** as it is making bubbles. Thinking I paid R299 it's not worth my money I went back to Mtn vangate Mall today Sunday 9 September 2018 and got Shaun again. I explained when I bought the phone along with the screen guard in March. He looks at me and says you hear what you saying, you bought it six months ago obviously this will happen. Really for R299 the other lady goes on saying it does this in heat as if my money means nothing it was **** customer service they didn't want to help me because he told me he can't refund me or give me a new one he can only sell me one. If I pay R299 for a piece of **** plastic that's supposed to be better I expect my money's worth. Thank God I didn't change to MTN and just bought my phone there in Cash by the way, I paid almost R6000 including this piece of **** plastic screen guard. I want something done I want my refund.