Hi @ckiyan: do you still have this problem? It resolved for me after I updated the post-upgrade database (see: [Solved] Some contributor list articles disappear after upgrading from ojs 3.1.2.4 to 3.2.0.2 - #18 by ji_farquharson). The metadata associated with the article submission (including email addresses) was no longer linked to the article after an upgrade. It might be worth checking your author table to ensure that there are no NULL values in the publication_id column.