I can see from your post that you see a green tint on your iPhone X. This is certainly not expected behavior and we'd like to get to the bottom if this with you. Do you recall when you started seeing this? What happens if you restart your iPhone? Are you on the latest iOS 11.1.2? Does this tint seem to appear using certain apps? If so, which apps?
Check out the link below for information that may help with this.
Get help with the display on your iPhone, iPad, or iPod touch
If the colors on your display appear distorted
If the colors on your display seem distorted, you might need to adjust the color filters. Learn how to use Display Accommodations on your iPhone, iPad, or iPod touch.
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