Poor After-sale Service

I bought a Nissan X-Trail 1.6 diesel as a demo model. The car has done 103000 km's and went for a service. First one out of service plan, but within Extended warranty. I received a call that the front lower control arms have cracked rubber bushes. It apparently is not covered, but falls under normal wear and tear. I logged a complaint with Nissan SA and received a ref number. One month later no call from BB Nissan. Called Nissan SA again on 17 March 2020. To date no call received. I did some research and the bushes should on average last at least 100 000miles(160 000kms). Not a lot of km's done and almost all on tar roads. If a 4x4 is equipped with poor parts and very little is then covered by the warranty then why pay dearly for services if the extended warranty is worth so little. The control arms is replaced at a cost of R9000 by Nissan and if you do this with any other dealer you loose the warranty. Nissan just lost another client.