Adsl lines down

Absolutely terrible service. Have a Telkom 4mbps uncapped wifi contract with them but I honestly cannot get 4mbps second. Right now I get 1. 82mbps and upload is 0.40mbps And when ever weather is bad the network goes worst. What can Telkom do to rectify this ****py service I am receiving from them. Waiting to finish contract term and move over to another service provider.