Hyundai vehicle services

I have been to Hyundai Pinetown on 30 January for 45000 km service I reported a popping sound when braking and turning right, they fixed it according to them. A week later the sound came back I tried to contact dealer principal with no success, logged a complaint online on the 5th of March, you only send Automated response via email and no other response. So I booked the car again in Pinetown for that popping sound on 11th of March Chasandra was assisting me, with this assessment now they told me, my coolant is rusty need to be flushed for R1000 + and aircon need to be fixed for R400 and with the popping sound there is no fault my tyres are wearing unevenly. Those tyres are brand new. So I phoned customer care and spoke to Elizabeth she advised I speak to a my dealer, I then phoned Rayan service manager he then took my number and car registration on the same day and said he will phone me back. But he never showed any care and integrity and never phoned me. On the 16 of March I find out on of the lock nut in my rim is missing and the three left are not tight they open with no effort at all, spoke to them but there deny touching wheels when the car war there on two occasions.