Good luck. They might only have 7 years. How to Access prior year online returns
https://ttlc.intuit.com/community/prior-year-return/help/how-do-i-access-my-prior-year-return/00/27010
If you can't get the side menus to open up to access the prior year..... You need to start entering some basic Personal Info in 2022 for the side menu to open up. Just continue a little ways into 2022. I had to go though about 12 screens.
If you used the Desktop CD/Download program then the only copy is on your computer and not saved or stored online. So you need to make and keep your own backups.
Or request a transcript from the IRS
https://www.irs.gov/individuals/get-transcript
Or get a copy of your return using form 4506
https://www.irs.gov/pub/irs-pdf/f4506.pdf
the Federal State Exchange (FSE) unit is an Illinois Income Tax Division that uses the federal tax information exchanged between the Internal Revenue Service (IRS) and the Illinois Department of Revenue (IDOR). in 2015 you filed a federal return with Illinois source income but Illinois has no record of you filing (NF).