Back Market review: Faulty phone. Back market refusing to repair, replace or refund.

Purchased mobile phone Samsung Galaxy S20 Ultra (Dual Sim, 128GB) through the Back Market platform, Refurb seller Cov Tech Ltd . Purchase made 15/06/23 with debit card online payment. 08.11 phone developed a faulty screen that was all lit up & flickering, and I was unable to switch off / reset / see any of the screen information. Immediately contacted Back Market through their online help linked to the order details, specified the problem, sent pictures of the malfunctioning phone and returned the phone as requested.10.11 Back Market sent a message to say that the phone had been received and the screen was malfunctioning because I'd mishandled it and listed general warranty exclusions. None of these exclusions apply since I'd not mishandled it. Photos they have sent which "evidence" their claim of mishandling, show the outside of the phone, simply of the screen not working. No evidence of mishandling. They are refusing to repair, replace or refund the faulty product, even though it is within 6 months of purchase and it hasn't been mishandled. The deflect from responding to my direct questions or points made and deflect from acknowledging their legal obligations to consumers according to the consumer rights act 2015. I've repeatedly requested that my complaint is escalated to someone who is willing to acknowledge and act in accordance with consumer legal rights, however again, their response deflects with "don't worry, your complaints are taken into consideration by our team" and request my address so that they may return the faulty and unusable phone. Order number: [protected].