This error also pops up when the value ‘MyKey’ is not ‘MyKey’. If you follow this Key tutorial, you see where the value ‘MyKey’ is set Signing Android Projects for Release on the Google Play Store with Unreal Engine | Unreal Engine 5.0 Documentation
The ‘MyKey’ issue is apparent after the build shutdown and above the error you find this:
FAILURE: Build failed with an exception.
UATHelper: Packaging (Android (ASTC)): * What went wrong:
UATHelper: Packaging (Android (ASTC)): Execution failed for task ‘:app:packageRelease’.
UATHelper: Packaging (Android (ASTC)): > A failure occurred while executing com.android.build.gradle.internal.tasks.Workers$ActionFacade
UATHelper: Packaging (Android (ASTC)): > com.android.ide.common.signing.KeytoolException: Failed to read key Key from store “D:\MyProject\Intermediate\Android\arm64\ExampleKey.keystore”: No key with alias ‘Key’ found in keystore