Bad service

I am highly upset. i bought a TV from Pnp Hyper Brackenfell on 23/01/2021. Exactly 30 days later the screen comes loose from the frame. i return the TV and am told by a very rude salesman that I have to wait for my refund as they need authorization. I email their head office but no one has contacted me. My issue is why must i wait for a refund when my relationship is between myself and PNP not the supplier!!!!!!!!!!!! When the sale was done last month the service level was excellent but now that there is a problem I have to deal with this non professionalism!!!!!