If you have set up Managed Metadata on a module and nothing is appearing in new documents you can follow the steps below to troubleshoot this issue.
- Open the Modul > List settings > Managed metadata and ensure that the "Enabled" box is ticked.
- Ensure that the right columns are selected under the "Manged metadata fields" section.
- Open up a SharePoint management shell and run the
initialize-wpmanagedmetadata command. - Try to remove the "Enabled" tick from No.1 > click save > refresh the site > Set the "Enabled" tick again and click safe.