My W-2 box 12a was corrected for 457(B) contributions taken back (neg in 2022) as I entered a different pension plan. I can't enter this neg number in turbo or freefile?

You say you have already paperfiled, so why are you trying to do here? Amend your return? Is this a corrected W-2?

No, generally, it is not correct to have a negative number in box 12.

   I had my W-2 corrected to reflect the money which was removed from my prior retirement plan by my employer in 2022. The money was moved into another retirement/pension plan when I got another license, moved by my employer. I did not do it, they did. Therefore it  was not a rollover on my part (as the IRS tried to say when I called).  They originally had written the same number for last year without the minus sign so it looked like I had double (same amount for 2021). I did not want the IRS to think I had double the amount when I had none in that plan for tax purposes and required withdrawals later.

  I did not file yet but the neg number for 12a (G) (which is correct) is not able to be entered so I thought I would do a paper return if needed to be able to enter the neg number. That was suggested recently when I spoke to a  Turbo tax expert for advice. However, I called the IRS today and they said it would be changed to 0 anyway so I will just say 0 and hope for the best. thanks, cmarchet45

Entering Zero should work and is a much better option than filing a paper return. 

Keep the W-2 and all tax forms with your tax files.