One thing that many people don't know about debt collectors is that they purchase unpaid debts for just pennies on the dollar that is owed and then collec the entire amount  of the original debt.  It is profitable but I see them as bottom feeders.
As soon as I moved to my present address ten years ago I got a new phone number.  I started getting many calls for a certain woman from at least three collectors.  I still got calls up to the first week of January this year (2015).  I answered that one and gave the caller a piece of my mind and told him in a very loud voice this is not her number and I'd be looking to the possibility of filing a lawsuit.

What is the name

Call numerous times but never leaves a message.  Wish I knew how to stop these annoying calls.

Block the number

These people knew the exact amount of my social security check. Wanted to know if I had a mortgage and how much it was. Presumably the amount being asked for is due to a hospital bill that did not turn charges in to my medi-gap insurance. They even have the wrong medi-gap Insurance company listed.When I stated they had the wrong insurance company listed, she stated that I ought to give her all of the information on the insurance card. These people call several times  day. I always answer.Smells like fraud.