NYS has 2 tuition grants. Students whose families earn $25k are eligible for the TAP grant which covers full tuition. They aren’t getting the Excelsior tuition grant because the TAP is paid out first. NYS tuition is ~$6k. When the $6k TAP grant is applied, the tuition balance is $0 so there’s nothing for the Excelsior to pay.
What does your package look like now? If the Pell, work study, and low income grant are only $7k, where’s the other $11k in grants coming from? Did those numbers change too, or just the Pell? You should probably call your school and ask for a one time reconsideration.