PLUS is not what you need to help you finish preparing your 2017 return. You are going to have to purchase and download the 2017 desktop software in order to finish preparing your 2017 return. You could call support and ask for a refund for PLUS.
Online preparation and e-filing for 2017 is permanently closed. You have to download 2017 software to a full PC or Mac (not to a mobile device) and then print, sign and mail your return. If you already paid for your TurboTax software, you can contact customer support to push a download of the software to you.
To call TurboTax customer support
https://ttlc.intuit.com/questions/1899263-what-is-the-turbotax-phone-number
They are available from 5 a.m. to 5 p.m. Pacific time.
To finish a prior year return started in TT online:https://ttlc.intuit.com/questions/2559403-how-do-i-finish-a-prior-year-return-that-i-started-in-turb
When you mail a tax return, you need to attach any documents showing tax withheld, such as your W-2’s or any 1099’s. Use a mailing service that will track it, such as UPS or certified mail so you will know the IRS and/or your state received the return.
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**