overly persistent call centre agent

I received a call tonight at 18:45, a time I find unacceptable for marketing calls. The agent told me I have been a Vodacom client for so long blah blah at which point I told her no, I am with Cell C for ages now. She proceeded to tell me that I ported my number and I am still on their call centre list and proceeded to try sell me a contract. I told her no thank you and to please remove me as I'm tired of all the marketing calls, to which she said she can remove me from her list, but I will still be phoned as I am with another service provider. I do not appreciate being told by a call centre agent that I wiil continue to be phoned when the CPA is clear that if I've requested it, they may not phone me again. Autopage, please send me confirmation in writing that I will not be called again, I have never and will never take a contract out over the phone!