first, continue to try to contact the IRS. keep trying. there is no guarantee that the iRS will honor the amended return and apply the $15K to it. then you will get hit with penalties and interest. something went wrong
online now only covers 2021 returns.
you might want to get a transcript of your a/c for 2021 to see if the IRS put your extension payment there.
did you put the extension payment on your 2020 it should be on schedule 3 line 9 which transfer to 1040 line 31
this may be a case for the IRS Tax Advocate office
https://www.taxpayeradvocate.irs.gov/get-help/issues-errors/incorrect-tax-return/
look under I still need help.
