Watch Connectivity
If you're trouble syncing information to the watch from the phone, open Settings > Watch Troubleshooting and it will run a series of tests to see if there are any connectivity issues.
A few things to try if the devices aren't connecting: - Restart the watch (press and hold the side button and the Digital Crown simultaneously until the Apple logo appears) - Make sure both devices are up to date - the versions sometimes need to match to connect properly.