Is Thrifty running a **** on customers deposits?

Booked a vehicle online end of May and paid 50% deposit. When they couldn't supply the vehicle the booking was cancelled. They agreed to reverse the payment within 3-5 days. It is now 6 weeks notwithstanding numerous calls and promises that the payment has been made. Nothing to date. I suggest anyone making a booking with Thirty not do so online or pay a deposit in advance. They are in the habit of taking customers money, failing to supply a promised vehicle and then holding on to deposits. The staff at Thrifty's branch at Radisson Blu Sandton (across from the Gautrain station) are complicit in this **** because they are unhelpful and uncooperative. Probably the same modus operandi at other branches? I would not recommend their service!!!