Please copy an example equation which shows this problem from your notebook to your computer's clipboard,
create a reply to this message,
click on the <> near the right end of the second line above the reply box to enable pasting Mathematica code
and paste your expression into the reply box.
Then post that and verify that it is displayed as in your notebook, edit if needed until it is correct,
the color hilighting may not be the same, but verify that all else is the same.
Make certain that the example is simple, but includes all information needed for someone else to understand it.
Then someone else can reverse this and put your code in their own notebook and try to determine why this is happening.