You may be able to get a vocational expert to assist in your case to prove that your spouse is underemployed. Please see the following article for more information: https://www.robinsonandhenry.com/colorado/family-law/colorado-child-support-attorneys/. Likewise, if your financial circumstances have changed and your case has concluded, you must file a post-decree modification. Please see this article for more information: https://www.robinsonandhenry.com/colorado/family-law/changing-child-support/ It's always wise in these circumstances to have your case evaluated by an attorney.
The foregoing information is general advice only and should not be relied upon to take, or fail to take, legal action. No attorney-client relationship is formed by this information.