This number called with a call display of "Unknown Name" and asked for my date of birth before they would tell me what they wanted. Of course, I refused to give my date of birth to some "Unknown Name" phoning me up out of nowhere. If they are a debt collector their conduct is unprofessional, as only the vulnerable who need protection from a debt collector would give their date of birth to someone over the phone without verifying that that person had any business knowing their date of birth.