If you have already e-filed or mailed the return, you will need to wait until the IRS has accepted it. Once they accept it and you have received your refund, then you can amend it to add the 1099-INT. If it gets rejected, you can just make the needed changes and file again.
After you have received your refund, you can go here and get instructions https://ttlc.intuit.com/questions/3061514 for amending that return.
If you have not already filed your return, you can use steps here below to jump to that section and add the 1099-INT. You can use these same steps if you have to amend the return.
https://ttlc.intuit.com/replies/3300478