The problem has to be a corrupt character in the 1099-B itself.
On the browser go to Tax Tools, Tools, Delete a form and delete the 1099-B and any supporting worksheets
Then add the 1099-B again
Type it in yourself, do not import it
Computers can put a hidden character in a field and it is impossible to find it by reading it.
Here is a TuirboTax article on 1099-B
