Even though a rollover distribution would have no tax effect on
your return, you should include it
as part of your tax return in order to file a complete and accurate return.
Since you have already filed, once your return has been accepted
you can file an amended return to include the information on the Form
1099-R.
If you choose not to file an amended return, you may not
suffer any consequence, but it is possible that the IRS would contact you for
not including the 1099-R on your return.
Here are the instructions for amending a 2017 tax return.
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