Incredible Connection sold me a faulty IMac

I bought an Apple IMac from Incredible Connection on a 3 year contract in 2019. When I got it the seal Canal Walk was already broken and I asked the sales person why. His response was a customer wanted to take a look. I naively accepted this explanation. In 2020 it wouldn't switch on. I took it in and they fixed it. In August this year red lines appeared on the screen and they replaced it. I got it back now and the internal microphone and the Siri function is not working. I emailed the shop and they said I must bring it back for more repairs. I asked the Apple store in Canal Walk if this was normal for a Mac to give such issue and they said no unless its a refurbished one. I was advised the same thing by the IT guys at our work as we use the same machines. I asked the manager Amien from Canal Walk if it would be possible to get a replacement as I work from home. I don't get paid if i dont work. They said its not possible as it is out of warranty