Unrealiable and upsetting

Yesterday I checked in online for my Kulula flight MN618 dep 06:00am from King Shaka Airport to OR Tambo Airport. I was allocated a seat and printed my boarding ticket.

So this morning I get to the airport and I am told that I no longer had my seat and it was allocated to someone. This turn of events upset me big time. I do not think it is acceptable for Kulula to do this to people. Last night my flight got changed from 6pm to 8:35pm and now this.