Rental service pathetic

I have 2 weeks in December peak holiday time that I have given to Ngwenya to rent out. I also advertised it privately, I got a client that wanted to book but Ngwenya told us the week was already booked by them. We told the client the week was taken. The next thing is when we spoke to Ngwenya again they told us that the week they booked was cancelled and it was empty again. How can they do this ? I am losing money because of Ngwenya's poor management

I have had previous situations like this before and I think the admin system needs proper management and proper control. I am really disappointed and would like a Answer from Management why a Top Gold Crown resort cannot rent out my weeks.