FastJet or SlowJet???

I am writing to you regarding flight FN8335. My booking reference for this flight was SH8GCN. This flight was scheduled to depart from Harare International Airport on 4th December 2018 at 19:00. However, the flight was delayed and did not arrive at Johannesburg International Airport until 23:15 meaning it was 2:35 late. I feel the communication of the ground staff was very poor to say the least. The only communication received was “the flight is delayed due to technical reasons, and feedback will follow”. No further feedback was communicated even after several enquiries to the ground staff. No effort was made to ensure the comfort of any passengers that was stuck at the airport. I am a regular flier to Namibia, Botswana, Mozambique and Zimbabwe to mentioned a few and found this delay caused great inconvenience and was handled unprofessionally. Please be so kind as to respond to my complaint by return mail, that I can consider my future choice of airline for these destinations. Should you require any further information or would like to discuss this further, please feel free to contact me.