These places are also trading on your phone number. When they call they can also determine if you are likely to pick up the phone,  they guess at your gender and age (and then can sell the info to other telemarketers),  and finally-- as long as they have a number being dialed it appears that "work" is being done.

If they removed all the wrong numbers, there would be so few legitimate calls for them to make,  they would have to close down.

I always offer that if they want to verify my identification,  I have a police detective that I work with, (be ready with your local police department number and address) and if they call and provide their federal EIN number,  he will send out a fraud kit to them identifying  the private number they are calling does not belong to the name they are calling for.
The calls usually stop after that.

I received a call from this number last night.  They asked for my brother. We do not even have the same last name, so I do not know how they even got my number.   I told them he does not live here, nor does he  live in the state.  They asked if I had a good phone number for him.  I told them I was not going to give that out.  I was then told they have a number for him but, they just wanted to make sure it was the right one.  I told them well, if you have a number for him, call him!!!   I have gotten these kind of calls in the past for him, and truth be told, he probably owes money, but they need to call him, not me!!!  

571-261-0021
Got this call twice and I called back.  The call shows up as told  receivables performance-...  then says well remove this from the list...

receive an average of 5 calls daily -- looked at previous internet postings and most people have reported this problem back in 2008 -- looks like they just got my number -- sorry they did!!!!!!!!!

Quien llama, no dice nada, no deja mensaje y habla los domingos hasta 5 veces !