Disingenuous SAA! Business class ticket, economy seat!

I booked a business class flight from JHB to PE on the 13th December 2025. A very expensive flight. Only to get to boarding and be told of a seat change because of an aircraft change with no other explanation or apology. I ended up squashed in a seat (row of 3) with economy class passengers - not enjoying any differentiated benefit of having paid a higher fair! No apology, no explanation. Just an expectation that you must accept because you need to travel. Never flying on SAA again if customers are taken for granted like this! Why sell business class seats for an economy ride? This is false advertising, and a *****ulent business model to make more money at less cost!!! NONSENSE!!!