Click through button that resets at any stage?

#1

Basically I have a button that changes the status column of that row to the next status (Not Started, In Progress and Completed) and it also assigns the user who pressed the button to the ‘Worked on by’ column.

However, when i change the status back to ‘Not Started’ i want it to remove that user from the ‘Worked on by’ Column. If this makes sense?