Turbo Tax is generating form 8606, but I think this is incorrect. I have a traditional IRA and a Roth IRA. The entire contribution to my traditional IRA was deductible.

In 2017, I received distributions from both my Traditional IRA and my Roth IRA (because I returned to school full-time and needed the money). 

I didn't make any contributions towards my IRAs in 2017.

I know that all of the money in my traditional IRA is taxable because I didn't pay taxes on any of it.  But, 3/4 of the money in my Roth IRA is from after-tax dollars (the other 1/4 is the profit).

Why is Turbo Tax generating Form 8606?