To many phone calls per day

I have cancelled my policy with King Price and they still contact me every day, some times I get 3-4 calls from them after I told the numerous times to cancel my policy and stop phoning me. It's so annoying when they still try to speak to me after I have given them a written cancelation. No man why phone people so many times per day?? I was really happy with your great service but now this is just to much calling me unnecessarily.