Automatically declining calls when connected to CarPlay

Starting a few months ago, my phone began automatically declining all incoming calls when I am driving and connected to CarPlay. This was not the case before. I could previously receive incoming calls. There are no other functionality problems w CarPlay. Music is connected, maps, Siri, send and receive text messages, etc. The only problem is — ALL incoming calls are automatically declined. I will see the incoming call flash on both my iPhone and the CarPlay screen for a moment before it is declined. Any suggestions?