Renault Clio gearbox

The gearbox locks between 1 and 2 and wont go into reverse. This started a year ago and the car has been with Renault Vospers Plymouth, for over 60 days and this time its been with them for 37 days. They deny any fault but I've had 2 surveys and both say there is a fault. The second survey has condemned the car as dangerous and not fit for purpose, as a result my insurance has been cancelled. The Ombudsman is dealing with the case as well as my solicitor. I have dozens of statements from drivers experiencing the fault, as well as examiners and other poor instructors driving the same car with the same problem. Renault told me that I was the only person in the country with the problem despite them denying there is a problem. Hopefully it will resolve itself before it puts me out of business!!!!!!
Any advice or anyone with a similar experience I would really appreciate hearing from you.