Terrible Customer Service and Rules with FLYSAFAIR

I am extremely dissaopointed with FlySafair. I had a flight scheduled with Kulula from Cape town to Lanseria on 15 june 2019. Due to the fog all flights were delayed with a delay of over 6 hours. I had to therefore cancel my flight to lanseria. Kulula is refunding me however my flight back with saffair is non refundable. They will do nothing for me who lost that flight and could not fly that day. They say i just forfeit my flight with no refund or no change of date allowed unless i pay penalties of which i had to do on the day only. This is extremely bad customer service and i will never book with them again.