Need help on Ohio SD-100X Amended SD Tax Form.

I have completed all of my taxes, but I messed up on the School District. So now I have to do the SD-100x. However, I am stuck on line 13 through 15. (link to form http://dw.ohio.gov/tax/dynamicforms/searchresults.asp )

On line 13, I am not really sure what its asking. As I understood it, its asking to enter the original overpayment and this amended return overpayment. However when I do that, it will deflate my return when I go to Line 14 to subtract line 13 from line 12. However if I leave line 13 blank (although the instruction states you need to enter the original overpayment), I get the correct refund I should be getting, which is $21

If someone knows the answer, or is willing to help me figure it out it would be very appreciated. I have called the ohio tax for the last four hours, but the lines been busy since. So. ...thanks!