Renault Triber Prestige

Hi I bought a new 2021 Renault Triber Prestige at Vereeniging When you change from Second to third gear, the car "breaks" then pick up speed. I'm not satisfied with that. I did bring it under their attention but nothing happened. I also wanted to take it back and get my old car back but that also didn't happened. Now I must pay for a car with I'm not satisfied with and nobody do something about it Please Renault advise me what to do