Had this happen today: The business contacted me because they had a worklist item they couldn’t release.

Sure enough, I looked and found the process instance in an “Open” status, but when I looked down the list of member worklists (under K2 Management, navigate to Workflow Server > Worklists), all of the members’ worklists showed their statuses as “Allocated.” An “Open” status would have identified the user from whom the task should be released. (I could have selected that worklist and clicked the “Release” button in the top navigation to restore the worklist item to the queue.)

My solution: send the process instance “back” to the same activity. Navigate the K2 Management interface to Workflow Server > Processes > {process folder name} > {process name} > Instances, then search for the Process Instance (Folio works well). Select it by clicking on the checkbox to the left of its row, and clicking the “Goto Activity” button in the top navigation. Send the Process Instance to the same activity its currently in. This will effectively reset its status to “Available,” making it free to be worked.