2015 is no longer supported and you can no longer get a 2015 refund.
TurboTax online and e-file for 2018 ended on Oct 15, 2019. 2018 (and earlier tax years) can now only be completed using the CD/download software installed on a Mac or Windows computer. The return must be printed, signed and mailed.
2016-2018 software can be purchased here:
https://turbotax.intuit.com/personal-taxes/past-years-products/
You can download blank form from the IRS website for free.
**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.**
