Box 10 on your W-2 form should indicate the total annual amount of your Dependent Care FSA deductions. When completing your tax return, you will need to attach a Child and Dependent Care Expenses form (Form 2441 for a 1040 return; Schedule A for a 1040A return). One possible reason that the refund "decreases" is that it might be affecting your child care credit. Try going through the whole program and see if the calculations altogether balance out. Sometimes if you're not done with the whole section the amount showing as a refund/amount due at that point in time is not what the end result will be.
