I received a GV voicemail message from a number I didn't recognize. The person leaving the message said someone had called the number. I don't know the person. My phone definitely didn't dial the number. On top of that, my phone didn't ring and the number isn't registered as a missed call. I can't see any reason why I would've gotten this voicemail. I use Google Voice specifically for voicemail forwarding and have never used my Google Voice phone number. Any idea what the issue could be?