If you have entered or started to enter a Form 1099-R that needs to be deleted, go to the Wages and Income > Retirement Plans and Social Security > IRA, 401(k), Pension Plan Withdrawals (1099-R) section and click Start or Update. This should show you a summary page of all Form 1099-R that have been entered. Click Delete or the trash can icon next to the one you want to remove.