If you do not have
access to your prior year return, you can request a free online transcript of
your 2017 tax return from the IRS. If you are needing your 2017 AGI, the transcript will include the amount listed on it. Use this link: IRS Get Transcript
Here is more
information on where to find your 2017 AGI on your prior year tax return:
https://ttlc.intuit.com/replies/3301618