Never rebook with Airlink

I booked return flights September 2025. Cancelled the tickets and was told they will only refund R176. Opted to rather rebook it within the following year. Today wanted to rebook and was told the penalties amount to R1389 for a ticket I purchased for R1100. I can buy a new ticket for R1280. When I asked the two ladies I spoke to, they felt it was fair that I pay penalties that is more than my original ticket and a new ticket. The explanation is "airport taxes paid last year was R220 and with the ticket available online it is R50 so I can't qualify to book the flight I have to rebook a more expensive flight". Why not charge me the additional R170 taxes and the rebooking fee of R575 (which is also ridiculous). If I was told that from the beginning, I would've rather used the tickets but the best response I get is "terms and conditions". I can't think that this is legal. I cancelled my flight 17 September 2025 and had to follow up numerous times and only received feedback 10 November 2025. Why not be upfront with customers and tell them at the time of cancellation that all these extra absorbent fees will be charged.