No due care to customer property

I have had the worst experience with the Autobody Company. I left my car with them on the 4/06/2019 for repairs due to accident and was suppose to be finished on the 18/06/2019, when the time came for me to fetch the car I was told it was not ready and will be finished on the 21/06/2019, when that time came again the car was not finished and was told car will be ready 26/06/2019. On the 26/06/2019 I call again and car not ready will be ready next day, when I call the next day I am told that the car is not starting when I left the car with them is was starting properly and they had to drive it from the parking to the workshop. Now they car me to find out what to due as though I was in the car of the car for the last 3.5 weeks..? What Nonsense service is this, I left he car in a working order and now in their care the car stops to start and they was me to explain.. utter nonsense. I will also be reporting them to the industry body for body repairs.