Kulula cancelling flights

My mom and I booked tickets from Joburg to Cape Town for 19 August 2019. On 20 May 2019 (a whole 3 months before this flight) we tried to cancel the booking online. There is no place to do so online. You have to phone, and then the lines are so poor you can barely hear what they say, and they refer you from one phone number to the next.

When we booked our tickets, we opted for the insurance part as well, paying extra for it. The reason why we had to cancel the tickets is actually not important, because 1) HOW many times has it happened that a flight is OVERBOOKED by the airline? Countless times. And then passengers must just accept it as "it's the way things are done", which is absolute nonsense, and 2) this is being cancelled 3 MONTHS IN ADVANCE, which means there is more than enough time to resell those tickets, most probably at a higher cost than what we initially paid for them, so the airline would make a double gain.

It's absolute nonsense that airlines don't refund. Our reason for cancelling isn't death or anything like that, but even so it is still a valid reason, as it is just as much out of our control as death. The touring company we're touring with cancelled the tour we would have gone on, so we now have to cancel our flight (we were to fly back from Joburg to Cape Town on our own). It's R582.11 each, for crying out loud, it's not going to make Kulula bankrupt. They'll probably end up selling these ticket for double that price. We have already lost a lot of money because of something that isn't our fault, and this will go a long way to helping us cope with this financially. My mother is a pensioner who never really travels, this was supposed to be a treat for her. And I'm under 30, still living with my parents, so this was supposed to be a treat, but now it's turning into a nightmare.

Please, I don't want to fight, but every cent helps. We are not cancelling because we don't feel like flying anymore, it is really events outside of our control. Maybe it is time for airlines to become more client-centric, and maybe it can start with Kulula setting the bar. All the other industries are doing it, why not the airlines?