If the return is rejected because you did not use the IRS issued IP PIN then you need to get it from the IRS so you can successfully efile or you will need to mail in the return.
You should have received a new IP PIN from the IRS by mail in either December 2021 or January 2022 to be used with the 2021 tax return being filed in 2022.
Go to this IRS website to retrieve your 6 digit IP PIN - https://www.irs.gov/identity-theft-fraud-scams/retrieve-your-ip-pin
