Try these steps in order:
- Turn the contrast theme off, then reapply it.
- Go to Start > Settings > Accessibility > Contrast themes.
- Set Contrast themes to None and select Apply.
- Then select Night sky again and select Apply.
- Windows may briefly show Please wait while the colors change.
- If Night sky still shows the wrong colors, create a corrected custom contrast theme.
- In Start > Settings > Accessibility > Contrast themes, select Night sky.
- Select Edit.
- Check these items and change them as needed:
- Background
- Text
- Hyperlinks
- Inactive Text
- Selected Text
- Button Text
- Use the color picker and brightness slider, then select Done.
- Select Save as, give the theme a name, then select Save and apply.
- Use the keyboard shortcut to confirm contrast mode is toggling correctly.
- Press Left Alt + Left Shift + Print Screen to turn contrast mode off or on.
- If the display still looks wrong after restart, switch back to the default Windows theme, restart, then set the contrast theme again.
- Go to Settings > Personalization > Themes.
- Under saved themes, select a default Windows theme.
- Restart Windows.
- Then go back to Settings > Accessibility > Contrast themes and apply Night sky again.
- If the screen is still showing unexpected colors such as yellow/white, also check that color filters are not enabled.
- Go to Settings > Accessibility > Color Filters and make sure they are turned off.
If the issue is only that the contrast theme does not persist after restart, the most relevant built-in fix from the available guidance is to save the corrected colors as a custom contrast theme with Save as and then Save and apply.
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