H4 stamping with 14yrs and 9yrs andmyself

I am stuck here, could someone help me, I filled DS160, I wanted to fix appointments, but confused, i have login created for three of us in same page, 14yrs old needs to go in person MUST, myself and 9yrs old have drop box options, but while entering CGIFEDERAL, it asks me are you under 14yrs old and next page it says did u get stamped when you were exactly 14yrs old in your passport.
I am confused, need help how to proceed with fixing this.