Faulty cable

I bought a HMDI to AVG cable from Kaysies on 28/10/2023. When I got home, I connected it only to find that it is not working. I tried to phone them the following Monday, the telephone number on the slip gave an error message. I took the cable to our IT department who confirmed that the cable is faulty. On Friday, 3/11/2023 I sent my husband to get a refund on the cable as I can't do anything with it. They refused to do so. Hence the cable is still in it's original packaging and I have the slip. It is unfair to sell faulty equipment. They did not even test it in front of me to see if it is working. I want my money back.