Sold my vehicle - still registered in my name

I traded my Spark in at Provincial Motors for an Aveo in April 2015. I had lost my logbook but the sales lady, Promise, said she will sort it out and I don't have to worry about it. In October 2015 I received a call from the Sales Manager, Pieter, who asked me for my logbook as he has a buyer for the vehicle. I explained to him what transpired in my conversation with Promise and was surprised that the vehicle was still registered in my name. Pieter assured me that he will sort the matter out and I need not worry. My Aveo's licence expired on 31st January 2016 and I went to renew it at the licencing department. Low and behold I was told that I could not receive my Aveo's licence because the Spark's licence (still in my name) needed to be renewed first. I immediately contacted Provincial Motors. They said they sold the Spark to an employee. They assured me they would get it sorted out. I've waited 3 weeks now and there has been absolutely no progress in this situation. How can somebody buy a car and not have it in his/her name??? Surely they have committed ***** by receiving money for a vehicle yet not registering it in the new buyer's name???