I would just let it go as it calculated. It may be that for some reason there is tax due on the 529 funds. Can I explain why, no? My guess is that is where the $2,200 is coming from. I also think because the $2,200 is taxable, that made enough available tuition to allow the full $2,500. You come out ahead $2,400 if the $2,200 is only costing an additional tax of $100.
Your $1,000 payment and books, etc. would have to be entered manually as I previously explained. I would not bother entering it at this time as you received the maximum credit.
I am glad it worked out in your favor.
