Did the issuer of your 1099-B indicate that the second 1099-B was a "Corrected" 1099-B?  You may need to contact the issuer of your 1099-B to get clarification on why you received to 1099-B's for the same transaction.  

Code A indicates a short-term transaction for which the cost or other basis is being reported to the IRS. This code to report a transaction that the recipient will report on Schedule D (Form 1040 or 1040-SR), line 1a, or on Form 8949 with box A checked with totals being carried to Schedule D (Form 1040 or 1040-SR), line 1b.

Code X is used to report a transaction if  they cannot determine whether the recipient should check box B or box E on Form 8949 because the holding period is unknown. 

The "Corrected" box is not checked - I will call the issuer and ask them why I received two forms.  Thanks for answering the question.

if you have two 1099-B, neither marked ( C ), you have two transactions as far as IRS is concerned.
That's not good.

If the sum of proceeds matches what you actually received, Never Mind.

You sold two lots.