Hey good morning.  If you deselect "efile" from worksheet and save the file it should remove the return.

I have never had any luck with having that disappear no matter what I tried - and I have tried suggestions offered in this community.  Luckily it doesn't happen often for me so it is only minimally irritating.

Unchecking the EF boxes on the Fed Info worksheet should remove it, BUT if you had an extension that was EFiled and accepted, I think its stuck there since its got EF Data embedded in it.

I have had them stuck there without e-filed extensions.  Sometimes they just don't go away no matter what you try.

Did you un-check states, too, go to each state, then Save and Close?