Thrifty Car Rental has pathetic customer service

I rented a car on 3 September at Cape Town International Airport branch and up to now I haven't received my deposit. I am frustrated about their service. They even asked me to contact my bank as if they don't know the proper procedures to be followed. The customer services tried to help and when I followed up, I was told that the accounts department was not giving feedback. Surely, this is grossly unacceptable!