Shocking / Lack of Customer Service

Easily booked my ticket over the internet, no problem. Purchased a more expensive ticket which includes one free change to your booking on condition that you pay in any difference in fees.

Have been trying to change my booking for two days - not possible on the internet and when you phone any of the "manage my booking" or "customer care" lines no one answers. And no listed e-mail address for correspondence.

Please then tell me Kulula, how then must I change my booking? You are breaking your own terms of the contract we entered into upon purchasing of a more expensive ticket which advertises one free booking change.

Very frustrated / disgusted / upset.