Broken promise

I rented a car at Triftty East London Airport on 20-22 August. I requested for a print out of an invoice upon returning the car. I was advised it will be ready the following day. I asked for the invoice to be sent to my e-mail address, which was never done. I called at 17h30 today (friday) and was told that the accounts department is closed. If I have to wait this long for a mere invoice, how long am I going to wait for my deposit refund?