Graco snugride sunglock extend fit 35 infant car seat help

Kayla • Mommy to two beautiful little girls

So I have this car seat for my daughter who is 4 months old and the headrest part is cause for my daughters shoulder to be to snug in the headrest part does anyone have this car seat and know how to mice it up or take it out. I can't find my manual. This it the scree part it has what I don't know what kind of tool this is.