1099-R taxable amount is appearing as 0 taxable amount on 1040. What is going on here?

What is the code in box 7 of the Form 1099-R provided by the payer?
Is the IRA/SEP/SIMPLE box marked?
Does box 1 show the same amount as box 2a?
Is box 2b Taxable amount not determined marked?

Did you accidentally mark that you did a rollover?

Thanks for the responses.   I checked, and did not mark that it was a rollover.  Box 7 has a 7 code and yes the IRA/SEP/SIMPLE box is checked.  Also the 2b taxable amount not determined is check but 2a shows taxable amount which is the same as 1 (gross distribution).    If I uncheck 2b and/or remove the amount on 2a, nothing changes or recalculates on the return.  I would LOVE to file this with no taxable distribution on the 1040 but I believe this is wrong and would eventually catch up with me.  I could file this way because the return is showing "no errors".  Thanks for your help.  I tried to figure out who to contact at turbo tax but cant find any way to do this.

Try deleting the 1099-R and then reentering it, being very careful that every part of your entry process is correct.  Sometimes that will work in these situations.

I suggest that you delete the 1099-R and re-enter as shown below.  Unless you have previous non-deductible after-tax basis in the IRA then the box 2a amount show be on the 1040 line 4b.

Enter a 1099-R  here:

Federal Taxes,
Wages & Income
(I'll choose what I work on - if that screen comes up)
Retirement Plans & Social Security,
IRA, 401(k), Pension Plan Withdrawals (1099-R).

OR  Use the "Tools" menu  (if online version left side) and then "Search Topics" for "1099-R" which will take you to the same place.

Be sure to choose which spouse the 1099-R is for if this is a joint tax return.
Be sure to pick the correct 1099-R type:  Standard 1099-R, CSA-1099-R, CSF-1099-R, RRB-1099-R.

[NOTE:  When you get to the "Your 1099-R Entries" screen where you can add another 1099-R, use "continue" to keep going as there are additional interview questions after that screen in most cases.  You can always return as shown above.]

Thank you all for your input.  dmertz did the trick.  I had stopped giving non deductible IRA contributions years ago and forgot that they would be part of the calculation in the first MRD.  I kept looking for the data source but it never steered me to the 8606.  SO glad for you out there!

If your IRA year-end value drops below your non-deductible basis, (a sad state of affairs), you will not pay any tax on your RMD.

@dmertz is an IRA genius!

If deleting and reentering does not produce the correct taxable result, it might be that you have indicated that you have basis in nondeductible traditional IRA contributions that exceeds the amount of the distribution and you did not indicate a nonzero year-end balance in traditional IRAs, resulting in a zero taxable amount being calculated on Part I of Form 8606.  Check your tax return in forms mode for this Form 8606.

Be sure to click the Continue button on the Your 1099-R Entries page and confirm that all of the follow-up information is correct, including your basis in nondeductible traditional IRA contributions and, in particular, you year-end balance in traditional IRAs.