Okay - this is confusing. You say you donated the stock ‘this year’ which is 2024 (last time I checked). Then it’s not mentioned on your 1099-B - which would be for 2023. So did you donate the stock in 2023 or in 2024?
You need to have a receipt from the charity for the stock showing which security, the number of shares, and the value as of the date donated. Then, on your tax return, you will need to take a deduction on Schedule A and your deduction is limited to 30% of your AGI, although you can carry forward excess deduction amounts for up to 5 years.
I will also point out that if you had not held the stock for at least 1 year and 1 day before you donated it, your deduction is limited to the purchase value, not the value of the stock on the date that it was donated.
IRS Pub 526 p526.pdf (irs.gov) has information about charitable giving.
AJ