Make the Assignee field mandatory whenever a user transitions an issue/ticket into a new workflow status.
Currently, users can change the workflow status of an item without assigning an owner.
When a user selects or transitions an item to a new workflow status:
If Assignee is empty, prevent the status change.
-> Prompt the user with a message such as:
“Please assign an owner before moving this item to this status.”
->Only allow the transition once an Assignee is selected.