Search for REI Systems yielded this on their contact page: "If you are contacting us regarding spam calls from 703-956-8779, they are not legitimate calls from REI. We are working to fix this issue now."
I started seeing calls from REI Systems on a couple of "work" cells, as well as my home phone. This is an obvious spoof - see: https://www.reisystems.com/ They are a Government contractor and presumably wouldn't be involved in this sort of shenanigans!