I think you're referring to an IP PIN (Identity Protection PIN.) If the following is your scenario (did son claim himself?), you would need an IP PIN in order to efile your return. If you don't want to do that, then your other option would be to print, sign, date, and postal mail your return.
Is this your situation?
Did you try to efile, and your return was rejected because your son had claimed himself on his return? Even though your son amended his return, yours would continue to reject. BUT you now have a way out so you can still efile, and it involves getting and using an IP PIN. See this:
New this year:
If a dependent mistakenly indicated no one can claim them and causes a rejection of the parent's return, the IRS now allows the first-listed (primary) taxpayer (such as the parent) to get an IP PIN (a 6-digit Identity Protection PIN) and still successfully efile their return and avoid having to file a return on paper. The dependent still has to amend their own return, however, to indicate someone can claim them. I have seen users in this forum where it has worked. and the parents efiled successfully.
"Beginning in the 2025 filing season, the IRS will accept Forms 1040, 1040-NR and 1040-SS even if a dependent has already been claimed on a previously filed return as long as the primary taxpayer on the second return includes a valid Identity Protection Personal Identification Number (IP PIN). This change will reduce the time for the agency to receive the tax return and accelerate the issuance of tax refunds for those with duplicate dependent returns. In previous years, the second tax return had to be filed by paper."
"In the scenario where the dependent has already been claimed on another tax return, the IP PIN provides an important new option. The taxpayer listed first on an e-filed tax return claiming dependents can provide their current year IP PIN when they file. If they do, the return will still be accepted. The spouse (if married filing jointly) and the dependents on the tax return don’t need to provide an IP PIN if they don’t have one."
IRS Source:
https://www.irs.gov/newsroom/irs-takes-steps-to-help-prevent-refund-delays-by-accepting-duplicate-de...
