Telkom bad internet service

Telkom is the worst internet service provider. I pay for n 4mbs line and cosntantly I have a line speed below 1mbs. I logged a call in the week when speedtest showed 0.44mbs, I did nother speed rest totY and 0.56mbs. Telkom just cannot offer what thy promise. I am tited of having to log calls. Sort it out. Please.