Caller ID said call came from Seal Beach, no message left. I took off my caller ID and called back since it was a local number. A recorded man's voice said the number is "unallocated." Either the message is legitimate (I've never reached this kind of recording before) and the number hasn't been assigned, in which case it seems that it must have been spoofed, or the caller recorded the message to prevent incoming calls. In either case, this sounds like a scam. The number is now blocked.