After you file

If you did not put any amount on Line 28, that was an error.

If you want a refund,

contact Customer Support.

You can't get a refund through this forum

next time, whichever tax software you choose,

print a copy of your completed tax return for your records, and review it carefully before e-Filing.
You will need it if you are audited by the IRS, or to amend if a TurboTax update changes your return or for any other reason,
SUCH AS, correcting Line 28.
AND, to find your AGI next year.