Homeloan Insurance

I cancelled my building insurance with the preferred provider by FNB, i changed to another insurer who is cheaper. They deducted R973 from me which was double the amount of the insurance through FNB. Nobody can tell me where this amount came from or what it was for. I just get emails saying the my query has been resolved but I have yet to receive a reason for this. This is very poor service from the Homeloans department, it's like trying to pull teeth.