After you file

What kind of 1099?   There are many types.   1099-DIV, 1099-INT, 1099-B, 1099-R, 1099-MISC, 1099-G, etc.

What do you mean by "additional income".   Are you referring to "other income", such as would be reported on Line 21 of your Form 1040?    Where is this income showing up on your return?