Appalling service from Discovery Vitality

In February 2020 I purchased a ticket to London using Vitality. When covid came I was immediately advised by British Airways that my flight had been cancelled. In due course I was issued with a voucher, valid for 3 years, for the value of this ticket. When I came to use the voucher BA then said that the voucher had been cancelled and I must claim my monies back from Discovery. I have now been phoning for the past 12 months and still have NO refund from Discovery. This really is the most appalling service from Discovery. We are now in 2024 and I still am owed more than R 16 000.00