Refund to voucher, unacceptable service.

I have had very bad experience with flysafair as before the lockdown we booked tickets, prior to the flights we have cancelled the tickets to refund to voucher, the consultant from the call center confirmed cancellation and assured me vouchers within 10 days, we have received one voucher about a month after that, till today which is 3 months later we still did not receive the other voucher, after several emails, they opened again on 8th of June and still the call center does not have answers for me. We need to book new flights for later this year.