Due to the "Keep application on top" setting of TWS, it is possible that one or more pop-up windows have opened behind your main TWS screen. This will prevent you from taking any action on your main TWS screen until the pop-up windows have been closed or addressed.
Try to press the Esc button on your keyboard a few times in order to close the hidden pop-up windows. You may also try reducing the window of the main TWS screen and closing the pop-ups manually.
Additional Information
- The "Keep application on top" setting in our Users' Guide.