Prius 4 voice dial stopped working

2012 Prius 4 with moonroof/solar/upgraded navigation.
Voice dial stopped working for me. Phone (iPhone 4) connects and contacts transfer. All aspects of Bluetooth work. Voice commands for navigation, etc work fine. But, will no longer voice dial. When you hit the voice command button on the wheel, it tells me to say a command. When I say dial+name, the screen says standby, but nothing else happens. I'm baffled!