I got the same message with a few variants. Threatening call from 888-974-4309 and from 888-721-4344.

Just got a threatening call from 888-974-4309. And also from 888-721-4344

“Hi this message is for …. My name is Emily Moore personal locator calling in regards to a document received in my office with your name and Social Security number against you. In order to avoid filing and also discuss the details pertaining to the complaint you will need to contact the mediation office of Mary Celisse. She can be reached at 888-974-3409. Failure to contact Mary Celisse’s office is going to result in a process server being dispatched to your residence or place of employment to serve you with a summons to appear in court. In order to stop further court proceedings you do need to contact this office as soon as possible. Again she can be reached at 888-974-3409…” Mary Celisse