Closed business in 2018 and filed final return 1120S. Did side work for some previous cleints in 2019 which they sent 1099-MISC for under my EIN. How do I file this?

[AnnetteB6]

You should first request a corrected Form 1099-MISC from the clients that reported your income under your former EIN.  It should now be reported under your Social Security number if you are operating as an independent contractor.  

The income will need to be reported on Schedule C as self-employment.  Enter it as 'cash' income since the Form 1099-MISC was reported under the wrong number, unless you can get a corrected Form 1099 before you file your return.

If there is ever a question from the IRS with regard to whether the income was reported, you can show that it was included on Schedule C.  

@epsylon9

[AmeliesUncle]

If they sent the 1099-MISC using YOUR EIN, you just report it as a business on Schedule C.  Or did you mean that they used the  corporation's EIN?