No one at TurboTax can tell you your 2019 AGI. Did you read the very long and detailed answer I provided another user just above your comment that outlines multiple ways to get the 2019 AGI? If so, what is preventing you from getting your 2019 AGI?
Here's a direct link to that detailed answer, which explains multiple ways to find it:
https://ttlc.intuit.com/community/taxes/discussion/re-i-need-my-2019-agi/01/2301383#M823418
