Afrihost - Bad Service

The service I have received with afrihost has been horrible. My modem is not working and my internet speed is not what I pay for. I have received no help and not even a technician has been sent after asking more than once that they send someone to sort it out. But they expect full payment for services that I am not receiving, I have a 100mbp up and down and don't even get half that speed on a fibre line