We had that problem here for the first year we were here. Every 3rd day, the same collection agency would call and ask for the same guy, and everytime, we would reply, "You have the wrong number". Three days later, he'd call back again. I tried polite, apologetic, quiet, loud, rude even funny a couple of times... nothing mattered, three days later he would call back. The phone company was ZERO help, this went on for almost a year. So we finally paid to change our number. Havent had a single call from them since... So peaceful... lol