Renew-it panel beaters

Worst customer service ever. My car was sent to them by the insurance for panel beating and repairs after it had an accident. I have waited 30 days. Till now as I am writing this email i have not received my car. I had to return insurance courtesy car as 30 days was finished. I was supposed to have received my car. This is the first time ever i have had a car sent for repairs and 30 days come and go and its not finished. They keep telling me stories. Same message for 3 weeks, your car still in assembly. I am so icovenienced , i am not able to do my travels. They can't even give me courtesy car. Worst customer ever. What must I do now? I have been putting pressure on them, insurance has been putting pressure on them, now story is :its we are still doing quality check. After 30 days ?? Its not acceptable at all. I am very very disappointed.