bad service from thryfty and nissan milllnerton

19 December I bought a used Nissan X-trail at Thrifty,Plumstead and serviced it fully at the workshop recommended by the dealer. On the 23 April 2015 I had a breakdown with the vehicle and they towed it from my house to nissan in Millnerton, since then we been up and down about who is responsible to fix the vehicle and even today they still want to blame me for the breakdown even with the report from the engineers that they can't say what could have caused the breakdown, the vehicle is now by their workshop for past 6 months stripped but nothing happening,thrifty even forgot about me and carried on with business as normal and I'm stranded with no transport! These two huge name company are not prepared to assist me at all, I went and purchase the car at thrifty because I thought since they are well knows establishment I will receive much better service and a high standards good instead to my surprise they are nothing close to that!