From being excellent to now just another SAA

If there was an option to give negative stars i would not even rate it that high. Safair use to pride themselves in giving good service. I made a booking for my dad that is an elderly tall person in December 2020 already for a flight in March. I paid for a premium seat. A week ago i was informed that my flight has changed to a later time and when I checked in I was given a standard seat. I called the help center and they just advised that they changed the flight and the seat was already taken.