Unable to make/receive calls on Apple Watch Ultra 3 when iPhone is not nearby or off.

I’m unable to make calls on my Apple Watch Ultra 3 when my iPhone 12 Pro Max is not nearby or turned on. Watch is running watchOS 26.2 and phone is running iOS 26.2.

My carrier is Verizon and I have the Number Share+ plan for the watch. No matter what I try, when I’m away from my phone (or it’s off) I get a call failed message when I try to make a call on cellular or when connected to WiFi with the watch. I’m not able to receive calls on the watch either.

I’ve tried everything from restarting all devices, disconnecting/reconnecting Bluetooth, turning cellular off/on in watch, and I’ve tried unpairing the watch from my phone and resetting and re-pairing. Nothing works.

However, cellular data works just fine. No trouble sending/receiving messages on the watch, listening/downloading music, navigation, etc. when away from my phone (or it’s off).

Any idea how I might fix this?