Unable to update to WatchOS 4.1

I own three Apple watches: a series 3 and two series 2’s. I have been able to upgrade the WatchOS to version 4.1 on two of the watches. But I can’t get one of the series 2’s to update. Originally I would get an error message on my iPhone saying it failed because I wasn’t connected to the internet. I rebooted the phone and now it just hangs at a screen that says “checking for update.” I’ve restarted the watch and phone several times. The devices are near each other and the watch is on a charger.

Any advice?