Call came in on line which is on the DNC list; I answered and heard background conversation but no one acknowledge my voice. I hung up on the caller.

I've rec'd multiple calls from this number and it's very irritating.  I tried putting my number on their DNC list, but that's a waste of time.  My number is on nat'l DNC list, but that doesn't seem to help either.

I cannot get my phone number removed from this telemarketer after repeated attempts.

Got a call, message said they had important info about my credit card account.  When a human got on the line, I said I didn't appreciate their tactic and asked to speak to a supervisor.  The human hung up on me.  I called the number back several times and dead air, not as much as a ring.

When you respond in ANY manner, they know they have a live number and will repeatedly call you or sell your number to other pests or both. If you have Caller ID, try this: Do not use voice mail or an answering machine. You will have a list of all numbers calling you on your log, so you can return calls to those people you know who have called you. After multiple calls to you without even an answering machine responding, they will give up. They'll think they have a roll-over number for a business, and that it will never be answered. Ha! Two can play this game.