This feature is blocking all calls from hospital for me. Even after turning all the relevant settings on and then off again, the calls are still ringing half a ring or not at all then going to voicemail. I tried resetting network settings but haven't tested behaviour yet since I'm now forwarding my calls to a more reliable phone... this is a serious bug, not sure if others are seeing it too.
I noticed the settings on the Phone app on other devices don't seem to sync, could that be the source of the problem?