In a monitor setup having monitor A as external and monitor B as built-in monitor where monitor A is setup as primary display.
When I unhook my monitor the dock is correctly place on the built-in monitor. Now when I reconnect the laptop to my external monitor A the dock will not revert back to the primary display. You need to change your primary display to built-in, apply it and then do the same process again for your external monitor.
Is there a way to fix this so that the dock is always displayed on the primary monitor?