Complain about We Buy Cars

I'm Hlubikazi Ntamehlo,bought a used BMW 1 series at We Buy Cars Aeroton on the 21st January 2021.I drove it for 3 months and 3 weeks then it had a funny sound coming from it.I reported the matter at We buy Cars and Wynand Pieters was assisting me.He referred me to Jag Auto Tech and I took it there on the 1st June 2021 but still it has not returned. I ve been pleading with both We buy Cars and workshop to speed up the process to get my car back but nothing.I was told the car had a turbo problem at We Buy Cars but at Jag Auto Tech am told that the car needed engen overhaul the turbo is fine.Then Wynand Pieters from We Buy Cars sent me an email showing receipt that they paid the workshop to fix my car but until date it has not returned. On the 17th August I was told they were test driving it has cylinder fault misfiring and cuts off then I sent an email to Wynand Pieters pleading with them to change the vehicle since it's almost 3 months without a transport and still paying monthly installment then he told me he ll need to compile a report for the cost of the car and will send it to his head office.Im not told the duration of the time the process will take and it's really been long since I have been patient. Please help me I feel Im not fairly treated as this matter has been dragging for too long I still dont have a transport and now using public transport and that's costing me a lot because I'm paying double.