Please make sure if Lava Directory Manager is up to date. 

If there is an update message, please update it.

Please go to dashboard.
Install it and also activate it. ( if you don’t know how to install, please have a look at this post. )

Please Visit JSON Scheduler Setting Page.

Enable Json Generator Scheduler and setup time when It will be automatically generated.

Then the last update ( generated ) time will be listed on Last update.