Nedbank is *****ing me around

So in February I went and took a home refurbishment loan at cashbuild, the loan goes through Nedbank. After the loan being accepted. I decided that it was not feasible for me to take so i went and cancelled it. I wrote my letter of cancellation and my documents were sent to head office. To my surprise my account was debited this month by Nedbank for the loan I cancelled. I contacted them and they said they did not receive my documents saying I want to cancel but they received their money back, fishy much? Anyway i resent the documents last week and still have not been repaid now i am busy calling their accounts center with no success. I will fight for my money till i get ut.