You can try something like this. It's the only way I've been able to generate the ability to put a code into IRS form 8949 column f and to adjust cost basis in column g. I hope it helps some.
Turbotax how-to:
Add investment--do not download from the brokerage.
Enter different way, choose 1099 B, add in bank/brokerage name, Yes to employee stock, Choose Yes or NO, as appropriate, for "sales sections" on the1099B question
To enable correct entry of column f and g in form 8949, enter 1099B by hand, choose, then choose Enter sales totals instead, press continue, fill in box 1d and 1e, then choose the check box "I need to adjust my total cost basis, then choose "B"--or your appropriate code, cost basis incorrect on form. This should give the correct adjustment to the cost basis in the form.
Turbotax will ask to upload the 1099B and other documentation using pdf upload option in turbotax
Before filing, check the actual 8949 Form, boxes 1e, 1f, and g. (Tax Tools, print center, print/save/preview return, search 8949, and check that it matches)
