@user17632779997 note sure there is a question there, but you may be confusing terms.
Tax Liability is your reported income times the tax rate for your state.
a non-redundable credit can reduce the tax liability but can not reduce the tax liabiltiy below zero.
a refundable credit CAN reduce the tax liability below zero.
a refund is the tax liability less withholdings, less estimated taxes paid, and les any remaining refundable credit resulting in a negative number. if it's posiive, then there is an Amount Due.
