first, let's review your tax return,
look where your children are listed and then WAY OVER to the right.... where are the checkmarks? under "child care credit" or "other dependent tax credit'
if child care credit, then it's an IRS error
if under 'other dependent tax credit', that is why you didn't get the credit.
post back which it is and we can go from there. I assume all children are under 17 years old??