SAMSUNG Buy and Get promotion ****

I received a voucher on from Samsung for buying their expensive products, I then tried to book a flight to Durban via OR Tambo for myself and my child and the voucher only accepted costs for myself and not for my child. I then tried to book a ticket for myself alone however have to come back via Lanseria instead of Or Tambo, however and there was no option on the FLYSA website to book both flights, their system prompted me to pay first before making the second booking. However when i tried to book i was told the Voucher is only for single booking, to top it all the FlySA call centre when you are on a call it talks about the fact if you use a Voucher the remaining credit can still be utilised on the next trip. This is very disappointing indeed, and the worst experience ever. You call both FLYSA and Samsung and the response is "Sorry Mam theres nothing we can do you forfeit the Voucher".