Return policy dispute. First get the facts straight before blaming clients

My son bought an expensive car radio last week. Had to return it because screen keeps blanking out. They don't want to refund and we ordered a new one despite the fact no refund has been done yet. Their reason, tampering. There was no tampering whatsoever. My sons explanation.: "The radio does not come with a bracket. And there was a green sticker over one of the holes to ***** the bracket on. How else do they expect it to be mounted if they put a warranty sticker right over the hole of the bracket". I sent them an email yesterday and this morning. No response as yet. Bad on their return policy. I think this is an issue between Takealot and the supplier. The radio was not opened or tampered with in anyway.