Uncalled for sales onslaught

For the past 2 months I have been getting a Minimum of 2 calls a day from Cell C's sales team I have been begging them to stop trying to sell me a contract I have begged them to take my number of there system I have been promised by some of them that they will action that for me to remove me I have had sales agents that get arrogant and rude I have had sales agents throw the phone down in my ear I have been terrorised by Cell C for the past 60 days every day none stop with out fail I don't want a contract I don't need one The consumer act is supposed to protect us against such a onslaught of Businessess selling your private information to other companies and then after that happens *******ly the consumer act is supposed to protect us when you ask nicely for them to stop calling me but it doesn't Cell C doesn't care they just keep going with the onslaught for the past 60 odd days twice a day how can this be legal