★How to restore the UCS icon to default style?

Issue:

The UCS icon is displayed abnormally as shown in the below image. How can I restore them to the default one?

Solution:

1. Click on View → 3D Views → Top to reset the view direction.
   
2. Or you can enter the command UCS, press Enter, and type W to reset the coordinate system to the World coordinates; then run the PLAN command and press Enter to plan it.