This is from Harris and Harris, a debt collection agency. If you really don't have medical bills, you should probably call them back and sort it out. Hospitals write off past due accounts to them
simple google search on this number brings it up as Agruss Law Firm - they say they are calling from Harris & Harris but that company has a different number - they are spoofing Agruss Law Firm number and using Harris & Harris name for FRAUD - THEY ARE SCAMMERS