I got the same call and other searches have indicated this is a scam.
Left a voicemail saying that a lawsuit has been filed in my name with the U.S. government. Something about how they tried to contact me in the previous six months "but we never got any response from your end." It's a robotic, automated voice. Obvious scam.
They are scammers!!! Do not give them any money
Washington Jul 13th, 2018
Received 2 calls from this number that a lawsuit had been filed under my name.
Seems fraudulent. Automated message about someone filing a lawsuit against the US Government on my behalf.