Kulula.com - Poor customer service!!!

I made a booking on Kulula.com to fly from Cape Town to Lanseria on 03 Oct 2019 and returning from Lanseria to Cape Town on 06 Oct 2019. On 16 Sep 2019 I phoned the call centre to enquire how much it will cost me to change the date to 02 Oct 2019 Cape Town to Lanseria. The attendant explained the cost will be more then R1000 per person. I then explained that it will be cheaper to just do a new booking for O2 Oct 2019. She then said that I will forfeit my booking for 03 Oct 2019 if I don't change the date. I did not change the date as we did not have any travelling plans within the next 6 months. I did a new booking for myself and my husband on kulula for 02 Oct 2019. On Sunday 06 Oct 2019 I wanted to check us in on line and could not do this on line. I decided to call the call centre to assist at 10h42. The call centre informed me that my complete booking was cancelled. I requested to be transferred to a manager as at no stage I was informed that my return flight will be affected. The attendant informed me that the manager was on another call and that the manager will phone me back. Untill now the manager never returned my call. We decided to rather go to the airport to sort out the mess before our scheduled flight for 19h00. We arrived at the airport at 12h50 and again explained everything to the attendant at the kulula counter. Again the attendant explained that the booking was cancelled and according to the notes on their system the no show policy was explained to me. I insisted again to speak to a manager. The attendant made a call to the call centre and then informed me that they will listen to the recording of where the no show policy was explained to me. She advised me that she will phone me within 30min. She called me at approx 13h00 and said they have listened to the recording and the no show policy was explained. I requested a copy of the recording but the attendant said the cannot give me a copy. This will be the proof that at no stage at all I was informed that my return booking will be affected. She then informed me that I did not forfeit the ticket of 06 Oct 2019 but I will need to pay for a flight change as the flight of 19h00 was fully booked. This means my tickets were sold again to someone else!! To change at MY cost added to R1200 excluding the admin fee per person. And bear in mind that we had to spend time at the airport from 12h50 untill we have a new booking. I then made a booking with mango to leave at 19h30. We had to spend the whole day at the airport due to this negligence. We always preferred travelling with kulula because of their customer service, but clearly kulula is no longer looking after their customers. I am doing a lot of travelling arangements for not only myself but also for a few companies. Kulula will no longer be the preferred airline!!