Phone broken within days

tonygayter

Ok so, I got a new OnePlus 8 Pro direct from oneplus, and within a week the glass back smashed on its own whilst in my pocket. I messaged them and they said they would repair it, now before sending it back I heard it pop again and looked and there were even more cracks (I say cracks, the whole back had basically shattered and gave me a glass splinter when I tried to get it out of my pocket). I have since looked up this issue and it looks like its a common problem with the back shattering for no reason or from very slight movement causing stress fractures. I have asked for a refund as I dont believe its fit for purpose as the back shatters and gets glass everywhere and is poor quality as its a known issue even from the previous model. 

They have since replied telling me Im a liar and have dropped it , now I know I didn't drop it. But what are my rights around this? I just don't want the phone anymore even if they fix/replace it as it will just happen again.