Does the 2017 8606 form show the 2017 Roth conversion information in part II lines 16-18? If not then you might not have indicated to TurboTax that it was a Roth conversion.
If the 8606 forms seem correct and you did not have any other 2017 year end IRA then I suggest that you call the IRS on the number that should be in the CP2000 notice and explain to them that this should be a tax free Roth conversion. If they want any follow-up documentation, they should tell you what to send them to prove it.
Even if you failed to properly enter the conversion, they might be able to fix it over the phone (or ask you for an amended return to be sent to the address on the CP2000 notice) - ask the IRS first.
**Disclaimer: This post is for discussion purposes only and is NOT tax advice. The author takes no responsibility for the accuracy of any information in this post.**
