reporting stock sale from multiple brokers for a same stock

I bought stock ABC in march 2019 using broker X. Then I bought stock ABC in April 2019 using broker Y. Then I sold the stock ABC in May with broker Y. I think Broker Y will report a sale in 1099B as symbol ABC sale date 5/1/2019 acquired date 4/15/2019 proceeds 200 cost basis 150 gain 50 short term. I guess I need to report this sale against the stock I purchased with broker X as FIFO.  Here is my questions: how do handle the trade reported by Broker Y? Delete the trade record and create a new one or Modify it with correction of acquired date and cost basis and new gain/loss or ignore it? Please advise.

Did you sell all of your purchases, from Broker X and Broker Y,  in May using Broker Y ?

you don't need to do FIFO; you can identify which lots you sold.  but once you pick one method you can't just switch to the other for convenience.