How does one get hold of you?????

It is impossible to get through to Kulula. My husband and I travel very often from JHB - DBN and back in a month, we can book online no problem, but when it comes to changing flights (if need be) it simply cant happen! I get as far as choosing the date I want to change to and then an error pops up! This happens every.single.time. So I resort to phoning the call centre, no one has ever answered! I have even tried phoning the number dedicated to international calls, and its the same thing all over again! We have had to drive to the airport just to change a flight! Its ridiculous... dont bother having a call center, and dont bother offering online changes! its false advertising!