The Windows schedule or Windows Timeline is one of the most anticipated features in the Windows 10 April 2018 update. Microsoft has been announcing this feature for quite some time, but has officially made it available this year.
The Windows Timeline feature should (logically) work normally after the installation of the new system, but unfortunately it does not happen to everyone. 
It seems that although the Timeline appears in the UI it does not save your activity. Here are some details that you should check if your Timeline does not work.
Note that the Timeline takes at least one day to gather your activity. So to see some activity you have to spend at least 24 hours from the update.
Check if Timeline is enabled
Make sure the new feature is enabled, ie you should allow it collection of your activity history. Open the Settings app and in the privacy settings select the Activity History tab.
Make sure that I select "Allow Windows to collect my activities from this computer".
Clear activity history
You may need to clear your business history. Open the Settings app, and from the Privacy tab, select the Activity History tab again. 
Under Clear Activity History do click on button Liquidation. You can do this even if Windows 10 hasn't had time to collect your activities.
Temporarily switch to a local account
This solution can be a bit annoying but it seems to work. Open the “Settings” app and from “Account Settings” go to “About.” Click on choice “Sign in with a local account” (not a Microsoft account) and you will see that in the local account Timeline will work fine.
You may need to stay in your local account for a while before switching to a Microsoft account. Many users report that switching to the local account will fix the Timelines that are not working, however you should use your computer for a while with a local account.
It should be noted that all the above Kompogianni solutions would not be needed if Microsoft did its job properly. The above solutions come from reddit and forums where too many Windows users try to fix their system after the last update.
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