Cannot get Hold of Sell Direct

Hello Peter I got myself an Wifi router and We have no Signal in our Area for this unit. I need to cancel the contract but cannot get hold of Sell Direct. I did send emails to their mail adresses, I phoned plenty of times but they just not answering. Please assist, i need to cancel the 2 year contract with them. Telkom also send them a mail to request to cancel on the 13 November 2017.