Frustrated customer

On 28 May 2018 I took a sample of a diesel pump which was faulty to Casseys Auto in Springs, East Rand. A gentleman by the name of Mark from the parts department assisted me and indicated that I should leave the pump with him so that he can assess it. On the same day late mid day I phoned to check the progress thus far, Mark indicated that he took the pump to Bongani Auto in Springs which is a s****yard and that I should check with Thys Senior who had the pump. I called Thys who informed me that he took the pump to Joburg at this stage I was very frustrated because no one informed me about these developments. To date the diesel pump has not been returned to me from Joburg and Casseys Auto is refusing to take the blame for this. My car is sitting at home with no pump because of Mark's incompetency and arrogance.