Jerking car and when collecting it from dealer the vehicle is not drivable

I booked my Jeep Patriot in for this jerking problem I experienced. This jerking happened when accelerating. About a month ago I had one of the foreman take the Jeep for a test drive and there was no jerking. I advised them that I'm booking the vehicle in to check out this problem. I drove the Jeep and dropped it of at Jeep Constantia this morning, 19th June 2019. They advised me that there is a bad shudder and they need to strip to check the clutch. I had no problem with the clutch as I advised them it was a jerk when accelerating. They advised that they need 2 to 3 days to strip and report to Motorite on the condition of the clutch. I drove home and while driving The gears weren't as smooth as when I drove it this morning. When I arrived at home there was no clutch at all. I tried reversing and the vehicle is not moving at all. How is it possible that I dropped of this car in a perfect driving condition and no clutch problem, and now I'm at home and I can't drive the vehicle. They would have advised me immediately if this was a clutch problem, the plugs were changed and still the shudder was there. Now it's a clutch problem when I dropped of the vehicle in a drivable condition, I can't drive the vehicle . please help