I got the same error on Xcode 12.0.1 and Xcode 12.2 beta2,
Application identifier of the parent app, "{team_id}." , is not a prefix of the application identifier of the app clip, "{team_id}.***.Clip"
My project uses CocoaPods, and after adding new AppClip target, I found new XCBuildConfiguration section in Pods/Pods.xcodeproj/project.pbxproj.
And I found PRODUCT_BUNDLE_IDENTIFIER was set to ***.Clip there.
I replaced the ***.Clip string in Pods.xcodeproj/project.pbxproj with the Bundle Identifier of the AppClip project, and then error has been resolved.
I hope it helps.
komei
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