Does a contribution to My SEP IRA reduce my self employment taxes in 2021

I am self employed as a sole proprietorship and the only employee. When I enter a contribution on line 19 of schedule C (Pension + Profit Sharing Plans) it changes the Federal Tax Due, and other amounts on Form 1040

 

I have read that a contribution to a  SEP IRA Does Not reduce self-employment tax. But in this example it does.

 

Please help - thanks in advance,

 

Tom