Unfair customer treatment

I bought a renault Clio few months ago at renault rooderpoort, the car was fine till 4 months after purchase it started developing issues of not locking, the vehicle is still under warranty and service plan, i then took the vehicle to renualt menlyn to get the issue resolved, they told me that it has an alarm system fault and i should remove the alarm which was fitted on it, i then went to an alarm fitment centre in hatfield, they told me that the car has no problem with any alarm and i should consider taking it back to where i bought it because the car is still practically new.

I then called renault in rooderpoort to explain to them what the situation of the vehicle that the vehicle is 5-6 months old and it doesnt lock, the pre owned sales manager at rooderpoort said i should book it at any renault around pretoria and the warranty will cover it because the vehicle is still under warranty and the problem it has sounds like a techinical issue.

I then booked the car in at renault hatfield hoping they could assist me and determine what is causing my car not to lock, they said the right door lock is faulty they then told me that they contacted the warranty and the warranty said they will not be abe to cover for the repair as the car went for a service a couple of months before, my problem is now I am stuck with a vehicle that does not lock, i cant go anywhere with the vehicle because it is too risky to park a car that does not lock, this is really frustrating me because when my car went in for service i did report the matter but renault menlyn could not determine the problem, now im being told to pay for it while its not my fault and the car is still under dealer warranty and motor plan, i then contacted renault rooderpoort wanting to speak to the pre owned sales manager but i am not getting through to him, i tried speaking to the dealer principle and everytime i call they say he is in a meeting and will get back to me, it has been 2 full months since iv tried contacting them for assistance on how we are going to solve my matter but to no avail.

My car is practically parked in the garage because driving it is not safe for me or for the vehicle itself, this car is only 7 months old but i am unable to get assistance to this matter, i am highly frustrated about this issue