People from this company have been calling my house wanting to speak with John Sparks, whom I don't even know, nor lives at my the number they call. They make no secret of the fact they are a collection agency and are calling to try to settle a debt. yet every time I am put on hold for 10 minutes then the phone hangs up on me. they continue to call, yet only leave me hanging on just to be hung up on. What can I do to put a stop to these harassing phone calls?