Aucor is rogues

Utter rogues. I have put a deposit r10000 to be included in an auction . My R10000 deposit allowed me to bid any car that I was interested in. It was an online bidding platform I have bid for a vehicle and receive an email stating that I was outbid I then starting bidding for another vehicle when I noticed both the vehicles was on my name before the Auction could finish I went to cancel a bid and was told that It would be done I need to speak to the Auction manager ( Gareth ) After calling and sending him emails I have no response I then got a response after a week they will take R5000 deposit and then I need to pay for another vehicle. I then received an email to make payment within 20 min otherwise the other R5000 is forfeited. Im uncertain to how this is even possible.