Mango airline poor service

I received a voucher as I was unable to travel in June due to lockdown . I have redeemed my voucher and have had to pay an additional R4600 for the same trip to Cape Town . To this day I have not received confirmation for my booking . I have called their customer services number several times again at my cost to no success. I have sent e-mails for assistance no one seems to comeback to me . Their website doesn't not seem to be working properly. I need to travel in December but I have no confirmation for that .