Here's the process in a bit more detail
I had a form called Department 1 tasks with list of tick boxes. I associated this with the help topic and logged a ticket (ticket a) .
I subsequently added 2 more forms, Department 2 Tasks and Department 3 Tasks. I associated this with the same help topic. When I now create a new ticket (ticket b) with that help topic the ticket appears with all three forms showing tasks for all three departments.
When I view the first ticket (ticket a) (created before the 2 additional forms were created and associated with the help topic) it still only shows the tasks for department 1.