App Store Connect issue ITMS-90129 keeps blocking upload

App Store Connect keeps blocking App upload by issuing

ITMS-90129: The bundle uses a bundle name or display name that is already taken.

So far I tried:

• Changing the Display Name, Bundle Identifier (even with generated Hashcodes to make sure that the names really are not taken already)
• Created alternative Profiles, Identifier and App in App Store Connect (also using the same mentioned hashcode)
• Tried these changes in the Xcode input fields (under 'General') and also directly modifiyng the Info.Plist
• Re-Exporting the project from Unity to XCode with the new naming (to make sure Unity is not writing some bundle id somewhere which is not visible in XCode)
• (Update) Tried to Clean the build folder based on minchaej suggestion

Additional information: The XCode project is exported from Unity and we're using Firebase which is installed via Pods.

I'm grateful for any hint where to continue looking - because I'm really running out of ideas. Thanks a lot for taking the time. Cheers vik

The solution for this (probably very Unity-to-XCode specific) issue was localization related:

I had to remove all but the English localization entry in the Localization section.

I'm not sure why there were other loca resources before (since we didn't set them up) but I assume these included an alternative app name which was causing the ITMS-90129 to pop up.