Press 4 to partially hide the sky, and press 6 to show the sky. But it's no use pressing 4 and 6 now. What should I do?

This may be caused by software failure or shortcut keys being occupied by other programs. You can try the following methods to solve it:

1. Restart Tianzheng Software: Close the software and reopen it to see if it can solve the problem.

2. Check shortcut key settings: In the settings of Tianzheng software, check whether some hidden and displayed shortcut keys have been modified.

3. Update the software: If your software version is too low, there may be some compatibility problems. Try to update to the latest version.

4. Reinstall the software: If none of the above methods can solve the problem, it may be the software itself. You can try uninstalling and reinstalling it.

5. If the above methods cannot be solved, it is recommended to contact Tianzheng Software customer service or technical support for help.