So I've been getting calls on my cell for several months from someone asking for "Dennis Chung." The voice sounds the same each time, and has gotten quite upset with me because I will not let a person I've never heard of come to the phone. I have tried to explain that they are calling a number that has been mine for over three years, but they don't believe that I don't know this Dennis.

This company calls relatives and make false statements about you putting them down as a references in order to gain information about you from them.  If no information is volunteered by the relative, they are then urged to have you call the number above.  Their deceptive nature is concerning as anyone attempting to commit fraud would do exactly the same thing.