Got a call from this unknown number and let the answering machine screen it.
They left no message and just hung up.
Caller ID displayed: L7 SERV CALL
I came here to double check the number, but got no result. However, when I then Googled L7 SERV CALL, I discovered that people had previously filed multiple reports for L7 SERV CALL, but under different numbers. So, it would seem that this person (or company) is spoofing and rotating its number all around the country, to cover their tracks.
Bottom line: It's likely a scammer or telemarketer. Either way, just ignore this number or block them.
You need to go to the setting for your cell phone. You have a block number or reject call setting. If you can't find this, call the tech support for your provider.