Hi and welcome to windows central forums.
This issue has been reported to Microsoft and we are expecting an app update to fix it, as it is quite evident that the current cumulative build did not fix this bug. This issue has present since the initial build of redstone update (AU). As of now we dont have any concrete solution to this as even after hard soft resets the app seems to loose its function and the live tile either gets disabled or is stuck on a particular date.
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