Capitial gains cost basis

[RHF2]

I have downloaded my brokerage account. When I go to investment summary, I am not able to click on my

stock sales.  One of our sales is missing a cost basis. How can I enter it manually, without have to manually

imput all my other sales.

[RobertB4444]

Scroll down to the investment income section under 'wages and income' on the federal return and click 'update' next to the 1099-B and find the one that you need to adjust and click on edit or review next to it.  Then you can look at each individual transaction.

@RHF2