Uploading new version of my app

Hi
I am trying to upload and replace a new version of my app. I don't have the original Xcode files so needed to rebuild the app from scratch. I'm using the same bundle ID but when I try and archive the app from Xcode I get an error message saying the application-identifier does not match the original, also I can't see any build options to choose from in iTunes connect. Was wondering if anyone could help?
Uploading new version of my app
 
 
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