Are you working in TurboTax Online Free Edition? If so, the Free Edition will not support IRS form 1099-B, IRS form 8949 or IRS Schedule D form 1040.
This may be the source of your problem.
The software will ask whether you want to upgrade to Premium version which will support IRS form 1099-B.
The IRS forms which are supported by each TurboTax version may be found here.