I was ******, not once but twice

I took the car after suspecting it has a mechanical problem. I drove it there, after I paid to collect it the car would not even move. I was left outside the workshop when they closed, I ended up towing it. I was then asked to tow it back which I did, I was told the diagnosis has been done and problem solved. I paid again but the car is still in a worst state then it was when I initially took it there. Worst service I have ever received and a complete waste of time and money. As for the money though, I want it back