British Airways Comair Call Centre is a nightmare

I have been trying to contact British Airways without any luck.

I am trying to change my flight before my flight tomorrow and I am unable to get ahold of their contact service. I am also not permitted to change my flight online. It has been a nightmare trying to get ahold of BA and yet Kulula agents who sit in the same office are always easier to reach.

My flight is the first flight out and I will be made to forfeit the ticket amount, yet they are the ones who are unreachable.

Help