Outbound sales agent

I've received countless calls from this company of which 50% of the time there's no response on the other line and the other 50% they're looking for someone I have never met in my life. I've requested several consultants to remove my number off their database. One consultant (male) assured me I wouldn't be called again, and I've received 4 calls since then. I'm tired of repeating myself to people who keeps saying the same thing but still does not follow polite instructions.