My 1099-R has a code 2B in box 7 so I entered it as 2 and B because there is no 2B listed. When I go to review it says that the code B is invalid. What do I do?

Code 2 is Early distribution (except Roth), exception applies.  Code B is Designated Roth account distribution.  The two codes are mutually exclusive so code B is not valid.  
Contact the payer of the 1099-R and get a corrected Form 1099-R.

Thank you

In the follow-up to entering the code 2B Form 1099-R, you must indicate that the distribution is NOT from a Roth IRA.  TurboTax needlessly asks this question which serves only as an opportunity to make a mistake in answering since code B already explicitly indicates that the distribution from a Designated Roth Account in a qualified retirement plan, not from a Roth IRA.

Go back and edit the Form 1099-R and correctly answer the question.

@dmertz I have a 1099-R with code 2B.  It should be an exempt early withdrawal of roth money from a 401k account, not from a roth ira account.  If I answer the question "did this come from a roth ira account" with a YES it gives me an error that I can't use 2B.  If I answer the question with a NO it lets me use 2B.  So is it right to say it didn't come from a roth IRA, even though it was roth money inside a 401k?  

@essary69 , didn't I already answer the question in my reply immediately preceding your question?  The code B indicates that this distribution is NOT from a Roth IRA.  A 401(k) is not an IRA.  You must answer No to the question that asks if this distribution is from a Roth IRA.