All your forms must be on your 2017 return. You would need to Amend your return to add this form. First you will need
to wait and see if your return is Accepted or
Rejected by the IRS. If the return is Rejected you can go back in and fix the mistake
without amending. If the return is Accepted
you will need to WAIT until you receive
your refund and then Amend.
Follow these steps
to amend:https://ttlc.intuit.com/replies/3288565
