Charged full Business class ticket for R300 online bid upgrade on two tickets

Received email to invite me to make an online bid for a business class upgrade for two passengers ,PE to JHB. I bid R300 for the two passengers. I received an email stating I was successful one way, and then another email while overseas that the bid was successful on the way back. Back home I discover that I am now charged the FULL BUSINESS class ticket price on both tickets. The domestic flight was therefor more than doubled for two passengers.

I have spent two MONTHS of Customer Service enquiries, and finally told that I bid the full price of a Business class ticket- to the cent-, on the upgrade. No proof of my online bid has ever been presented, and I have been shafted through every department all referring to someone else.

When I already have in my possession two economy paid up tickets, how can SAA conclude that I bid the full price of two Business class tickets for the online auction upgrade.

This is blatant *****....and I'm given the runaround first degree without any proof that I authorized this.