Who is this

I answered this call thinking is was a return call.  the woman asked for someone specific who was not here.  She said she was from a charitable organization with a popular name.  I have no way of knowing that for sure since caller ID said, "unknown'  She did not ask for a donation.

The number is from Anamosa IA, They called a few time here and no one was on the line.....Only reason I answered it was because my kids life in that town with there mother

Has called my Google Voice # twice now. No idea who it is, didn't recognize number, didn't answer. No message.

has now called my Google Voice # 4 times. Never left any message.