apple watch 3 won't send text messages when away from phone

[LINTHO26]

When I'm out of range of my iphone so that the watch is connected to cellular, it won't send or receive text messages. I can make phone calls, and I've confirmed that my phone is on. However the messages just time out after a few minutes.

[stef7]

Can’t send text messages on Apple Watch 3... |Official Apple Support Communities

How to use your Apple Watch without your iPhone nearby - Apple Support

To receive SMS, MMS, or push notifications from third-party apps on your Apple Watch Series 3 (GPS + Cellular), your paired iPhone must be powered on and connected to Wi-Fi or cellular, but it doesn't need to be nearby. You also need to be signed in to iMessage on your iPhone.