Safair sneaky

my anecdotal experience is Safair do not respond to complaints - so I'm not holding my breath but perhaps other travelers will be cautioned. we had a return trip George- OR Tambo for the dates 14/3/25 and 21/3/25. Booking reference KY03E flight FA251 for the return leg I went online after receiving the prompt from Safair to check-in online. I noticed that Safair had allocated seats 4B & 4C. my wife and I prefer isle seats. So I attempted to change the seat allocation and was asked ,via online, to pay a change fee of R40.00 I object to this because I never selected the seats allocated (per above) - so I'm being charged for a system process. No way acceptable