BAD BAD service

Booked a flight via a travel agent, had to cancel received a voucher from FlySafair. No problem. Went on FlySafair website to book another flight redeeming the voucher. No space on the website to enter voucher number. Tried to phone for 2 days no join. Finally got hold of someone, now they are informing me that I cannot redeem the voucher as I booked through a third party, which is an absolute lie. I want to redeem my voucher and fly to George. Your service is pathetic. Third party must have been my dog doing the booking