"After the pushback tug is connected to the aircraft, the parking brake has been released, and the wheel chocks have been removed. However, the pushback still cannot proceed. What could be the issue?"
This is now your normal workflow should be:• Open the GSX menu from the Toolbar icon only when first starting Ground services.• Don’t close it from the Toolbar while Ground services are performed, always use the Hot-key or the X icon to close the menu.• Always use the Hot-key to re-open the menu, and always close it either with the Hot-key or the X icon.• Close the menu using the Toolbar icon when you are done with Ground services, usually before take-off.