It might have been a temporary glitch on the IRS end. TurboTax just transmits you return as you entered it.
Last years self select pins will carry forward if you are using a paid version of TurboTax and transfer the previous years data at the start of the interview. Both the pins and AGI will carry forward. Once a new tax return has been stated then it is no longer possible to transfer data.
Here is a TurboTax FAQ for contacting customer support.
https://ttlc.intuit.com/questions/1899263-what-is-the-turbotax-phone-number
There is no phone support for free unless you upgrade to PLUS.
**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.**
