In 2020 I filed on a 1099MISC , turbo tax changed it to a NEC. I did not enter any business deductions because it did not instruct or ask me to. Now I did 2021 on the NEC and eneterd all the deductions. So now I get a letter from the IRS stating I owe self employment tax for 2020. Do I just write a letter listing all the deductions I did not file on or do I file an ammendment for 2020? Thanks for any imput you may have.