RCI are never able to offer timeshare exchanges

I have a time share at Kwa Maritane over the period of the Nedbank Golf weekend-----gold crown resort in prime time. I banked it with RCI some time ago and also pay my RCI fees regularly. I have been trying to get a week in exchange for ages. My points expire at the end of October and I have been requesting something for the past 6 months. RCI NEVER get back to me except on one occasion when I tried to contact them after hours----I was phoned the following morning and was promised an exchange. There isn't even a record of this in the file!!!! A few years ago, even without me having banked my unit, they let it out to someone else and claimed I had space banked it----my daughter had come out from the UK and we were looking forward to the week away but ended up sitting in JHB. Needless to say, RCI couldn't produce any documentation confirming my alleged banking, but I still lost my week.i am about to lose yet another week as they simply do not bother to fulfill their requests. Why are they not able to help me----do they give the prime units to friends and family?