You mist have net self-employed income minus the deductible part of the SE tax. That would be Schedule 1 line 3 minus line 14.
The maximum IRA contributions for 2019 is $6,000, or $7,000 if you’re age 50 or older by the end of the year; or your taxable compensation for the year which ever is less.
(Taxable compensation is generally wages that you worked for - W-2 or net self-employed income minus the deducible part of the SE tax, but can include commissions, certain alimony and separate maintenance, and nontaxable combat pay ).
See IRS Pub 590A "What is compensation" for details:
https://www.irs.gov/publications/p590a#en_US_2018_publink1000230355
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**