Why I cannot use 401K for retirement tax break?

I have 401K. After I answered the question "Is xxx covered by a retirement plan at work?", I got the page "It turns out you don't qualify for a retirement tax break.", it says "because of your income, you're not eligible to take a deduction this year". I don't get what it means. I think 401K pre-tax contribution has nothing to do with my income?