Charing admin fee for canceling ticket aftr 10 min

Hello,<br> <br> Today I searched for tickets from PLZ-CPT on Google Flights, and I chose to purchase a ticket on my desired date Dec 13. I clicked through to SAA's website and entered my information. On the confirmation page I noticed that my departure date was for Dec 27, not Dec 13. I had not been told of the date in the 3 screens leading up to the confirmation. I quickly called SAA, and after waiting on hold for 45 minutes was connected to someone that spoke broken English. With much difficulty and patience, I explained the situation to the inarticulate SAA rep and cancelled my ticket, opting to rebook online to avoid the R100 surcharge for ordering a ticket telephonically. Much to my dismay, I was told that I would be charged an admin fee of R350 for canceling a ticket. When I protested and asked how that would be possible for a ticket I only ordered minutes before (I thought there was a 24 hour window for a full refund), I was told that \the ticket has already been issued."I do not think that this R350 admin fee is fair in this instance"