You have to subtract 1/2 of the SE tax from the Net Profit. So if you have a Net Profit of 717 your SE tax is about $101. Half is $51. You have to subtract 51 from the 717 = $666 for the max you can contribute. You have to actually take the excess out of your ROTH account.
Look at Schedule 1 line 14. You have to subtract that from the 717 to get the amount allowed to contribute.
