Comair Call Centre Change in Booking

I recently booked a ticket for my Mother from George to Jhb via Kulula and then from Jhb to King Shaka via BA Comair. The flights are on the 25th of March originally at 8h45 from George and 12pm from Jhb. Both these flights were then changed by 30minutes later and then earlier making it impossible to board on the flight to Durban. We tried to change this booking time via Manage Booking but this was not allowing stating we must call the call center. We tried several times however with no joy holding for longer than 15 minutes. We were also refused entry at the George Airport at the Kulula office for assistance for Covid19 reasons. This is just pathetic service!!!!