Same problem, no solution rendered!

I have taken my car 4 times already for the same problem that I have been experiencing with my reverse gear. I've raised it with the dealership and also sent a complaint to Renault to rather have the entire gear box replaced as whatever they say they do does not seem to ever work, but they just won't change it, yet I pay so much money for the so called service of the car! Have sent an email recently to advise what they did last still did not work and no one responded, they don't take me serious :-(