Swarming Vultures Sales Team - 18 Calls in TWO Days! No Means No!

Telkom please sort your call centre out, seriously! I have had 18x calls from them over 2x days... Besides this impacting on my time, my cell phone is a business tool and I keep having *** flashing on my screen and INTERRUPTING my work calls. I have been civil to each caller, as it is not there fault. Or is it? What system do you have that when someone says 'no thank you, please remove me from your database', that your team STILL call. Are they not logging the feedback or is your system faulty? This is HIGHLY unprofessional and is a major infringement of my consumer rights. I asked to speak to a manager and of course they cut the call... no-one wants to take responsibility. This is reckless and rude. Is this really how you approach sales, like swarming vultures?