one option is to not import and put it in manually. if import is generating some massive 8949 form with all this transaction detail that you're having to validate, this is not needed, you can just manually input the summary level totals of your 1099-B which goes onto Schedule D.
If the 1099 shows any adjustments (e.g. wash sale, AMD) then you can enter those one by one to avoid being asked to mail stuff to the IRS, which will generate 8949 just for those line items and put the rest as summary level.
not a CPA/Expert- just my 2 cents if import is creating more issues and work than it saves.