Problems validating App with embedded frameworks in Xamarin.iOS

Question

I embedded a thirdy party framework in my Xamarin project following the walkthrough: https://learn.microsoft.com/en-gb/xamarin/ios/platform/binding-swift/walkthrough

Steps:

1. I created in XCode a Swift project including the thirdy party framework called AcmeFramework.
2. I compiled the XCode project obtaining a new framework called AcmeProxy.
3. In Visual Studio I created a iOS Binding Library including the frameworks as Native frameworks:

• AcmeFramework
• AcmeProxy

4. In my App Visul Studio project, I added the Binding Library as a reference.
5. I've used correctly the library in the code
6. All compiles correctly and runs correctly on iPhone
7. I created the Archive for iOS and is Ok
8. When I try to distrubute the package it brokes in the validation step:

Invalid Bundle Structure - The binary file 'App.iOS.app/Frameworks/AcmeProxy.framework/Modules/AcmeProxy' is not permitted. Your app can’t contain standalone executables or libraries, other than a valid CFBundleExecutable of supported bundles. Refer to the Bundle Programming Guide at https://developer.apple.com/go/?id=bundle-structure for information on the iOS app bundle structure.

I reviewed the steps many times. What's wrong with the process?