Brand new Chev bakkie clutch gone

Bought a brand new chev ute bakkie. Gearbox faulty. Dealer sent it for repair / new gearbox. Still same problem they want to to investigate further strip again. Told them its a brand new vehicle im not accepting this vehicle back i am demanding a new one. They dont come back to me. No communication. They dont want to give a new vehicle. If it can be repaired they will repair it. They say its not the customers decision what he wants. Their stories dont add up. I am getting lawyers involved. This is the very first brand new car that was nought and we sit with more problems than a second hand vehicle. Problems started before 1st instalment went off.