Bad after service by Dynamic appliances

Fridge wouldn't switch off. Got Dynamic out in July 23 to fix. In Oct 23, 3 months later, I realised that it again doesn't switch off. I have been contacting Chris for the last 4 weeks but just getting ignored. Worst is the fridge is only 4 and a half years old. They say they give a year guarantee on the work. It's not happening