Bad service from Hertz OR Tambo

I hired a car in August 2018 and until today i haven't received a refund. I have phoned few times and they kept on saying it will be deposited into the account. The last time i phoned i requested them to rather deposit into other account and the guy that I spoke to said the money has already been transferred it would reflect in 3 days but until today nothing I have received. We returned the car the same way we were given including full tank and I even asked the day returned it if there shouldnt be anything i sign to confirm that they said no. This is frustrating most terrible service ever. After so many months I still have to be chasing after Hertz