I just got the same call on my private cell phone. They left no message. When my phone rings and no name of a contact come up, I always let it go to voicemail. My 31-second message prevents robot calls from leaving a message and discourages telemarketers and scammers. I did not, of couse, call back.
"Please leave a message after this 30 second message and music. Leave your name, phone number, who you represent and a very short message on why you called. I might call you back. If you do not leave the required information, it will be like you never called. If you call back twice without leaving the required message, your number will be blocked and will neither ring nor transfer you to voicemail. Stay Blessed!"
Pretty much the same....I let my answering machine take the call (which I do with all unrecognized numbers on caller ID, and my message explains that it is due to telemarketers and scammers). They left no message. The Caller ID read "Cell Phone FL."