Poor Service from BB Sinoville

This dealership has sold me a car of 500000 that is defective on the fuel gauge..it only three weeks I bought the car and already experiencing such challenges..the car is only 36000 km on the clock ..they are refusing to provide with a courtesy car..the car was booked on the 31 March 2026 at BB sinoville which is the dealership that I have bought from..to rub salt to the wound I called Nissan SA on the 1$2 April 2026 for intervention and since the have promised to return with a case number but they are also quite..I was supposed to travel for the Easter but I am now stuck at home with no explanation from NissanSA or the bb sinoville dealership