I get a call from 800-291-4367 and when they leave a message I am to call back about "an important business matter" and to call 866-531-5020. BUT I have yet to call them back...maybe I should so they won't call me anymore? Or would that be stupid?

I have had it with these A$$h____s. They call everyday and never stop. Somebody tell me how to get hold of them and I will visit them personally if that is what it takes to have them quit calling my home. By the way what about the do not call registry. I'm registered ... they still call. Typical government BS

This number calls me every day.  They called one weekend and asked to speak with me.  I wanted to know where they were calling and what they were calling for but the person on the other end insisted on verifying my address and phone number before they would identify what company they were calling from and what business they had with me.  So I hung up the phone and have refused to answer any calls that come in from this number.  I feel that if you are calling my house then I have a right to know who you are and what you calling for.

This is a repeating harrassing call, leaves no message

Bad news.  I am fairly sure this is a collection agency.  The rules for leaving messages are limited as to what they can tell you.  That "important business" matter is typical for these leeches.  

If you can get a mailing address for them, you can send them a letter requesting that they do not call you anymore.  It is called a "Drop Dead Letter."  I have only done this with collectors that send me mail though it should still work.  It is a Federal Law that once they have been notified, they cannot contact you anymore.  

However, they will just sell your past due account to some other bloodsucking company so they can harass you.  The whole system is a racket if you ask me.

Yes, this is a collection agency called Transworld.  They collect many things like hospital bills and old credit card accounts.