Unfortunately,
you'll need to amend your return.
Please see the
TurboTax FAQ "How to amend (change or
correct) a return you already filed," below, for instruction on how
to amend your previously-filed tax return.
Also, note that, as of the date
of this posting, Form 1040X isn't yet available for filing. Please check back in a week or so.
https://ttlc.intuit.com/replies/3288565