Renault Car - faulty vehicle

We have taken a New Renault Triber and the vehicle Gearbox was over heating within * months of use and less than ****kms driven. We had taken the vehicle to return it to dealer but we were sent to service center where they repaired the vehicle and gave back but stil within a week the same issue arised. We were again sent to service center and no improvement in the vehicle. Now the vehicle is ****kms and this is the *rd time the same issue has arised. They are not ready to accept that the vehicle is faulty and blaming us instead. Its been more than a month now that we have not collected the vehicle from service center as we do not want the faulty vehicle and they are still forcing us to take it back stating it is repaired now.