This is a collection agency that harasses anyone on any known records of the individual they seek, even if you don't know that person, in order to acquire information to find that individual.  They will continue to harass you to no end even if you continue to tell them you don't know that person and they don't seem to care if you ask them to take you off their calling list.  Very unethical practices and they don't seem to care about the Do Not Call government policies.