On a user portal, we have implemented some sections to fulfill a customer requirement to have the opportunity to either open a case in its Review harness or jumping directly into one of its open assignments. To implement this, we just created a simple table layout that queries the DB using a data page to fetch all the case instances of the desried type, joins their pzInsKey with both Assign-WorkBasket and Assign-Worklist to fetch all the corresponding assignments (and their pzInsKey) and then shows the resulting list on the table itself. In one of the columns we then have a link control with an open assignment action that triggers on click event. Even if the pzInsKey of all the assignments are correctly fecthed in the property that the action references, users in PROD environment are randomly facing an error when clicking the link control: a "No Stream to Display" error is shown on screen and it keeps happening for every row of the table unless the user logs out and back in. The issue is not consistently reproducible for users and we didn't manage to reproduce it even once in our DEV environment. Not being able to trace an occurrence of the problem we actually have no idea how to debug the issue and find a root cause. Any idea about what could be a possible cause?