To delete a worker:
Click the Workers menu then select Movements.
Select Delete A Worker.
This works as long as they have nothing against them. If they have assignments or (Unpaid) timesheets you need to delete these first.
To do this:
Go into the Timesheet / Assignment.
Press CTRL+M to enter modify mode.
Press F3 to open the delete dialogue.
Press YES when asked.
⚠️ Important: If a timesheet has been paid, the worker can't be deleted.