Unable to board flight, yet booked and paid for

Sunday,11/10/15, i was meant 2 fly 2 Durban from Lanseria, 10: 20 am flight. Went 2 the check-in counters, the lady assisting me (Shanice Masemola), told me i could not check in bcoz the flight was full. I expressed my disappointment, and the fact that i had a family event to attend in Dbn at a specific time, hence me flying down that early on a Sunday morning. She then told me i had to wait & see if anyone ddnt pitch, bcoz i was FIRST on the prioirty list. Joseph (from the next counter) said we'd see whose passenger boarded the flight. The airport supervisor (an indian lady) was there the whole time, and not once did she intervene. Shortly after, a white gentleman can and made a big noise about him getting on that flight whatever it took. Moments later the guy was given a ticket to board & i was left standing there offered an undermining R400 voucher for my inconvenience, which i still find disgusting!!!! Surely race cannot still be superior to systems. My appointments were less important to the white gentleman irregardless of what was written on the priority list! IM STILL DISGUSTED! i have been a loyal customer for yrs bt it STOPS! i will post this on every social media!!!