Very slow to assist with warranty

My tv is 2 years old and stopped working, I did not have the proof of purchase byt did have the original box with delivery slip so I sent that, it took hisense 2 minutes on a saturday to respond why they are unable to assist with warranty. Eventually I got the invoice and sent it in, some time later after several phone calls, someone arrived and immediately said its the back lighting and the tv needs to go in, we received the message that the tv has been repaired but weeks later and still no tv? Clearly the product is inferior and they are reluctant to honor warranty we are phoning daily now only to hear that it will be delivered? Date of first contact 27/11/2021