Starting with version 9.40, you can only create an INSTEAD OF trigger on a view. You cannot create an INSTEAD OF trigger on a view created using WITH CHECK OPTION.
Consider creating the trigger on the base table of the view or create a table with the same schema as the view and then define the trigger on the table.
You can also receive this message if you issue the START VIOLATIONS TABLE statement or the STOP VIOLATIONS TABLE statement for a view. You must specify the name of a base table in both of these statements.