Hey there! Have had a similar issue after migrating ClockKit complications to WidgetKit. 🤓 You must enable App Group not only to Watch Widget Extension, but for the Watch app target as well. This should solve your issue (solved for me). P.S. I still have issues with WidgetKit complications not updating, even though Watch Widget Extension has access to the data: https://developer.apple.com/forums/thread/735352

Hello. Not exactly the same problem as the author has, but still "WidgetKit complications not working". After migrating to WidgetKit complications I can't make them update whenever data is changed in the main app. I've checked lots of docs and Apple sample code I was able to find, but neither mention what is the proper way to trigger WidgetKit complications timeline reload. With ClockKit we had a very clear way to do that. Any advice would be HIGHLY welcome! Thank you! 🙇‍♂️ See my question for full details: https://developer.apple.com/forums/thread/735352