iOS 17 beta 3 and watchOS 10 beta 3 are out! If you are not being offered watchOS 10 beta 3, go to the Watch app on your phone, choose General > Software Update, and toggle Beta Updates Off and then on (watchOS 10 Developer Beta) again. Toggling this setting works around a bug and points your device at the correct catalog going forward (the bug is fixed in Seed 3, so you shouldn’t need to do this after installing Seed 3).
https://developer.apple.com/documentation/watchos-release-notes/watchos-10-release-notes