"The phone company and the police" can't help you. You will need to dump your problem right on the collector's front porch. My long form advice for "not me" cases is found here:
http://800notes.com/forum/ta-34af6a034ba34b6/unending-collection-calls
I had been getting a call from this number on my cell phone for the past several days with a message saying "this call was for (so-and-so) and if I was that person" and on the message went. I would just hang up, I didn't care, I was not the person named in the recording.
I decided one day to call the number back and found it to be "Diversified Consultants" a collection agency out of Jacksonville, FL, (look it up online). When an associate came on the line I told him I was continually getting these calls asking for (and I mentioned the name of the person in the recording). He asked if I knew that person and I told him no, she must have given them the wrong phone number. He replied that he would remove my phone number from their system and he said I shouldn't receive calls from them any longer. We will see!
Your lucky I told these people that I was not that person and did not know who they were and they keep calling up to 3 times a day 7 days a week for months. I'm getting ready to complain to the phone company and the Police on Monday.