Frustrated with telkom

I dunno what to do,my telkom mobile contract ended 3rd February 2018,I emailed the cancellation form,about 3 or 4 times without any reply,contacted telkom mobile via Facebook message,they told me they received my form this was on the 3rd of March but nothing happened end of March I get billed again,send them msg again they tell me email to ********** this email address doesn't work.spoke to them again in April they give me a link to access my accounts the link doesn't allow me to cancel the contract,they keep on asking for the number on messenger but nothing happens.I really dunno what to do,I've been charged now 3 month over the 24 month contract,the level of incompetence is very frustrating.And they call themselves the best network in SA.