I already e-file my Federal return on 4/15, Now I find out I have missed report 1 1099int how can I correct that error?
Once your original return has been accepted and processed (you've received any refund) you can amend your return to include the 1099-INT.
Please see the instructions in this FAQ to amend your return:
https://ttlc.intuit.com/replies/7276601