You can enter $1 as the amount - it won't have any effect on your tax calculation (unless you have many of these) and will allow you proceed and e-file.
From another poster with the same issue:
You can either bypass/ignore the error (leaves the checkbox checked and "0" as the amount) OR you can uncheck the checkbox and delete the value in the box (leaving it blank).
The first choice is more correct, but since this is just a worksheet that rolls up into another form, those two choices should produce the same result.