These people call several times a day.  My husband called them back today and they would not tell them who they were.  He asked them to take us off of their list.  They called back later today and I answered the phone.  They wanted to speak to my husband who was not home.  I asked why they were calling and they replied it was confidential.  I said that I was his wife.  They asked me to "verify" the last 4 digits of his social security number.  I said I would not give them that confidential information.  They hung up on me.  I believe they got our name from the phonebook and are hunting down another man with the same name as my husband who doesnt pay his bills (this man's wife's name is known to me so I know they are not looking for us since her name is not the same as mine).  It is frustrating.