When there is an amount in box 11 of your W-2, TurboTax asks whether the amount in box 11 represents a distribution from then nonqualified pension plan. Answering incorrectly in your case will allow TurboTax to treat the amount in box 1 as being compensation that will support an IRA contribution.
Another possibility is that you are married, file jointly and your spouse had compensation that would support your IRA contribution.
