Kulula cannot refund clients for bookings cancelled due to the lockdown in 2020

My son traveled to East London in March. As his return flight was booked for a date during the lockdown, we had to book an earlier return flight as no agents answered the phones when we tried to change the return flight. Kulula booked the flight, had us pay for it, and then canceled both return flights. We enquired about being refunded and was told that a travel bank would be created but that we had to use the funds for other bookings. This was 7 months ago. Phoned this morning to utilize the funds for a booking in December and was told that EVENTUALLY a travel bank will be created, but we must now utilize the funds in 2021. I am not going to fly anywhere in 2021, but they refuse to refund us or let us use the funds that they have kept hostage for the last 7 months. The agent just kept on lying and eventually put the phone down in my ear. Please do not make ANY bookings with Kulula. it is clear that they are keeping on taking money without being able to provide a service and that they do not have funds to refund customers that paid for flights that they cancelled due to the lockdown.