Poor service

My steering wheel of a brand new KIA SOUL which I bought from Cristine Knight on 23 April 2015 locked on 15 May 2015. I picked up the vehicle on 20 April 2015 after Eugene van Der Walt, Technical Manager at KIA The Glen said that there was a problem with the connector plugged, all was fixed and this problem will not happen again. On the evening of 28 May 2015, the exact same problem happened again. Cristine is not replying to my emails anymore, I have not heard from them for almost 2 weeks, I have requested a new vehicle to be issued to me as this is what I have paid for. I have not yet received any other feedback except that I must log my complaint myself with KIA, yet, i purchased this brand new vehicle which has put the lifes of my daughters and myself at risk twice. I am asking for what I have rightfully paid for and for a fair decision and my brand new car to be given to me.