Faulty screen protector

Bought an Iphone screen protector as the Vodacom in Clearwater mall. A few days later my screen started giving me problems i never had before. It wont just go completely blank, for minutes. When i approached them, i was told that there is no warrantee on screen prortectors and there's nothing they can do expect leave the screen with them and they will return it to their supplier. They said its not guaranteed that the supplier will give me a new screen and they insisted that the problem is the actual phone screen and not the screen protector. Over the last couple of days, the issue worsened and i decided to remove the screen protector from my phone and i have NEVER ENCOUNTERED the problem again. Which proves that the problem was Vodacom's screen protector. THe issue is that, i struggled to take it out and when i finally did, i damaged it. But this wouldnt have been the case if they just replaced this nonsense of a screen back and not tell me stories. Utterly disappointed.