Travelstart is *******

I had ticket booked through Travelstart to fly to USA on 25 December 2021 at which time we were not allowed to fly to the USA due to the travel ban. 3 tickets cost me around R60k. For two weeks prior to the flight I failed to contact Travelstart to reschedule. It is impossible to phone them and you have to reply on them to respond to your emails or miraculously answer their WhatsApp messages. A day before the flight I phoned British Airways who contacted Travelstart to suspend our tickets. I immediately requested to shift the flight for a week later when the ban would be lifted and Travelstart quoted me R100k to make the change!!! The credit is still with them and am I currently attempting to use it on a rebooking. To fly end July they quoted me R147k to make the change, even though new bookings on the exact same flights through them would cost me R77k. I tried for mid August and they quoted me R59k to make the change even though new tickets would cost R54k. It sounds like they stole my R60k and now are trying to rip me off for new tickets.