Bad service from telkom

I took out a contract with telkom in 2016 april, when it ended i chose not to renew, i was advised to fill a cancelation form, i then sent it end of march, i was now surprised i still get billed, i even canceled r49 pm they were illigally debitting, tgey then decided to charge me a fee for this, i even sent the docs to their social media accout, they still have not cancelled, I want my money they illigally stole and their contract cancelled as per instruction.