1099-R entering for inherited annuity. Issue with percentage that is mine..

I received a 1099-R from my late fathers annuity. I received 25% of the payout along with my 3 siblings. When I enter the info in my taxes, it appears to be calculating taxes on the entire 100%. I switched the 25% to 100% and my numbers didn't change. Box 7 Checked 4-D.   I only received 25% of the annuity, what is it not updating this?