question regarding collections

Hello all. Quick question. Here's the scenario: after I moved into my rental house, a pest control company left a flyer on my door. I call them and subsequently hire them for $35/month or $60/for 2 months. No contracts, no written agreements. I just call them when I need them. So after about 6 months, my lease is expiring and I'm moving out. I call and cancel my service, no problems. A month or so later, I get a bill for service they say they performed after I called to cancel. There was no proof the guy came to the house to do anything, so I didn't pay it. NOw i'm getting letters saying they're sending me to collections and the credit bureaus. Can they do that with just a name? I have a somewhat common name, and they have no other identifiers such as date of birth/ss #. I'm open to all opinions/suggestions...