Annoying bill collector, harassing me over a medical bill, that the clinic cashed 9 weeks ago, paid in full. I tell them right off the check cleared Feb 11th and to talk to the clinic. Usually, they keep talking. I retired and have spare time.   I added them to my contact list so I can quietly mess with the caller, asking lots of meaningless questions. I ask for the full name of the clerk submitting the debt to them, the race of the collector, if their mom is married, what is the calendar in their part of the country (they are 22 miles away), when asked about resources to pay them I tell them I have only had one infectious sexually transmitted disease in my life but the doctor thinks the radiation cured me,  etc. Eventually they hang up on me.