Has happened to me 3 times. First it was Shadowheart so reloaded last save. Then Lae'zel twice. On the third time I just accepted the loss. In group menu could not add anything to Lae'zel inventory. When I went to a merchant her inventory appeared and could sell items. However after I exited the merchant the remainder of the items were still not showing up and could not add to her inventory. I made a save, exited game to desktop the reload the save and it fixed the issue.
