This is happening to me also, Laurel.  Months and months of these annoying calls.  I am registered on the "do not call" registry, but doesn't seem to be working.  I am going to try registering again.

Keeps calling me everyday at the same time. No one speaks when I answer and if I leave it and try to call them it is a busy signal.

keeps calling and hangs up as soon as i pickup. been doing it for months now.H4E6

This number has been calling a few times a day EVERY single day of the week.  I have spoken to them 2 times.  They make it seem like you talked to them "last year" and it is for donations This week it was helping teens, last week it was domestic violence it is obvioulsy a scam.  they tried to tell me that I agreed to donate money and that they sent a form to me earlier in the year and that I donated last year.  Funny, if I did I would've had some donations to add when I filed my income tax...I DID NOT AGREE TO ANYTHING nor did they send me a form.  One girl hung up on me when I said I was not interested and to quit calling, the other guy I spoke to I told him to take me off whatever "list" they may have but once again they are calling...who can I call to complain of harassment now?? It's ridiculous!