OK. Remember that short-term holdings (less than one year) are only allowed cost basis.
I tried it on both the Desktop and Online software.
Works OK for me. in both.
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IF you did hold that stock more then one year, Go back thru that donation again.
1) On the initial page that has check boxes....None of the above is checked....correct?
2) On the page with yoru dates of donation, values and acquisition , re-check that donation and Acquired date. Make sure you use the exact date format they require.
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IF it still doesn't work, give us the details on each of those entry fields and well try it ourselves.
It is working for me. (Use Desktop TT 2022.47.14.33)
Note that your deduction is limited to basis if you have not held the stock for more than one year. So if you typo the acquisition date to be within a year of the donation date, TT will correctly limit you to basis.
If that isn't what's happening there could be another bug.