My phone service (Windstream) has an option of * 60 which blocks their number from ringing your number again....love it...when they call you just let them be the last number that has called you ...you just dial * 60 and follow the directions on how to turn it on ,off and deleat their numbers from the list...I have 6 numbers on that list now...lol
I don't answer - they call once per week anyway. I have started to title the phone numbers that call repeatedly - as grubbers, annoyers, and so on. I suppose I'll keep doing that to make myself laugh. I don't answer any of them.