Why is the item demand plan not showing in the related records of item

AI generated answer (using internal Slack threads):

The item demand plan might not be showing in the related records of an item due to several reasons. One of the reasons could be related to the Vendor field. If the Vendor field is not properly set up or if there is an issue with it, the item might not appear in the demand planning reports. Another reason could be related to the number of items that you are trying to generate demand plans for. If you have more than 10,000 items, it might cause some items to not appear in the demand planning reports. Lastly, it could be due to the way the sublist on the Item Demand Plan screen is set up. The sublist is filtered to show only the demand for the current year by default. If you want to modify the list for a different interval, you might need to use SuiteScript to change the filter. However, please note that when changing a specific column field of the Item Demand Plan record in another year or date using SuiteScript 2.0, it is required to mix it with SuiteScript 1.0 as an alternate solution of Enhancement 522797. ****** Disclaimer: This response was generated by an artificial intelligence assistant based on previous conversations from multiple Slack channels, and may contain inaccuracies or mistakes. ******