It sounds like you are getting mail or email demanding that you call this number, but not saying why.

Its almost certainly a scam.  The paperwork for a real lawsuit is delivered by hand to make sure it goes to the right person.  The issuer never warns you because you might hide from the server.

Don't call the number.  Wait for the paperwork to arrive.  The paperwork will never arrive.

Scammers like to prey on senior citizens.  Congratulations on investigating it first and not falling for the scam.