Two possibilities:
Grants and /or scholarships are taxable income to the extent that they exceed qualified educational expenses to include tuition, fees, books, and course related materials. So, taxable income may reduce your refund.
Qualified educational expenses are deductible to the extent that they exceed grants and/ or scholarships.
The Earned Income credit is added to the refund meter as you enter your income and personal information.
As you lower your taxable income with educational deductions, you may lower the amount of your Earned income Credit, thus lowering the dollar amount you see on the refund meter.
The refund meter will not be completely accurate until you have entered all of your information including all income and deductions.