Left my semi-working refrigerator broken

Wellies refrigeration came to fix our fridge which was no longer cooling properly. At the time the freezer was still working. After they replaced a part, they recommended we leave the fridge off for one hour. When switching it on we were very surprised to discover that both the freezer and fridge were now entirely broken. Cash was paid for the service and I've tried many times to get hold of the company, with no response. Beyond disappointing.