8775233986 / 877-523-3986 Reverse Phone Lookup

This caller left a harassing message on my home phone number and said I had 24 hours to contact them back, that they would be serving me with papers between 9 - 2 today. They have obtained my sister's cell number who is an amputee and in a nursing home and have continued to harassed her with numerous phones calls and threats. I do not know how they obtained her cell phone number or my home phone number. When I called them back I got a man who advised this was a matter from 1994 and the papers would be served and I had better be home to receive them. I attempted to let them know I was returning their call and he begin screaming and claiming I called him. I have never heard of these people and would like to know my legal options in this situation. Thank you, Teresa Congleton