Let's see if I understand ... you filed a return with a balance due. Did you pay it ? Do you have proof of payment ? A cancelled check or bank/cc statement ?
And then amended the return to switch dependents which resulted in a no change 1040X?
And then you got a bill for the unpaid balance due from the original return ? Line 16 of the 1040X reports the amount you paid on the original return so it assumes you paid it unless you change that figure.
Look at the form 1040X …
Column A should have the figures from the original return, Column C the corrected figures and Column B the differences between the other 2 which needs an explanation on page 2 of the form 1040X.
If you completed it correctly you will see an entry on either line 16 OR 18:
On line 16 should be the amount you paid with your original return.
On line 18 should be the amount of your original refund you received.
Then you will see your extra refund on line 22 OR the new balance due you need to pay on line 20.
