Oh you said net income? Do you have schedule C for self employment income? If you have self-employment income you can only contribute up to your net profit reduced by the deduction allowed for the ER portion of your self-employment taxes. So you have to subtract half of the SE tax from the profit.
See IRS publication 590A page 6 about self employment income (it applies to both Traditional and ROTH IRAs)
https://www.irs.gov/pub/irs-pdf/p590a.pdf
