I think you meant ''attorney'', not that it means a real attorney was calling. You're right that a ''new'' phone number is usually recycled, and with it comes the flotsam of the prior holders. If the collector has no claim on you, send a ''cease communication'' notice via USPS Certified with return card. This is the method promoted by the FTC and many consumer watchdogs, who will explain how you can do some damage if that notice is ignored.

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Whether you are called a debtor or some collector thinks you can flush one out, you have rights and options. Most are simple to exercise if you only learn how. The FTC and the CFPB can start you on your homework. See also if your state laws grant additional or stronger rights.

official FTC guidance and staff opinions on the FDCPA, PDF copy of the Act

CFPB reiteration of the Fair Debt Collection Practices Act
 Sep 25th, 2012
I keep getting text messasges from this phone number. Referenicng a case # and to call this attorning.This must be fraud or credit agency. I have a new phon enumber so I must be getting the other guys calls.
 Sep 25th, 2012