How to respond to receiving a duplicate list of corrections Two weeks ago I have done and I have submitted the corrections that a journal had asked me to do, but today thay asked me to do the same corrections. I am looking for a good letter cover to let them know.
Perhaps the new version didn't arrive or they lost it. Perhaps the editor clicked the wrong link and sent you the wrong response. Write back that you made those corrections and sent them on date. Include a fresh copy of the new document. Ask for instructions on how to proceed if there is any difficulty. 

I suspect it is just a simple error. Make a simple and friendly response.