How to Add a Jira field to Issue screens in GanttTable?
If you encounter this error message when working with GanttTable, it is because the issue field type has not been set in your project settings.

Here is how to do it:
In Company-managed projects, you might find yourself unable to access the Issues settings. That is because you have limited permission in the Jira instance.
To solve this, you should contact and ask your Jira admin to add permission.