2014? And you are just now looking into it? If your 2014 return was rejected then it was never filed at all. At the time it was rejected you would have received an email telling you why it was rejected. You could have corrected the problem and re-submitted it, or you could have mailed it. I am not sure if the records will even go back far enough to indicate why your return was rejected. Your only chance to get a possible refund for 2014 is to finish the return and then print, sign and mail it to the IRS. You only have a few months left in which to do so--by April 17, 2018. After that it will be too late forever to get your refund.
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 received the return.
https://www.irs.gov/filing/where-to-file-paper-tax-returns-with-or-without-a-payment