Assuming it is Verizon, or Verizon related, according to another website.
I just received a call on my cell, but didn't answer, no message was left.
Googled the phone number, which brought me here.
Logged into my account, and sure enough, I am past due!!!!!
Oopsie. Paid it.
Got a call every day this week. Not one single message left! Be legit and tell me who you are and leave a message. Most people these days do not answer unknown callers.