Help Please

We booked 5 tickets for a round trip Cape town, Johannesburg and Harare and back. We spent over R28,000. We went through all the rebooking etc for two of the tickets and we were told we would be contacted once tickets have been re-issued. Its been more than a week and no call and no email and no reissue. For the other 3 we wanted to put the credit in their bank but no one picks the phone. Today they are just dropping the phone.HEEEEEELLLLLLPPPPP