if you filed in April, the AGI from the 2018 return should work. if not try 0 (zero) if that doesn't work contact support but even they may not be able to help. I can not say whether it is an IRS problem or a TT problem. There have been multiple posts where OP's claim the AGI is right but still get rejected. in such situations you can only paper file
don't know your tax situation but you may be able to use IRS free file
https://www.irs.gov/individuals
scroll down a little bit until you see the column labeled "FILE" then the link to efile for free
if you have a state return many states are also offering something similar on their department of revenue website.
