Hey make sure you have called:

func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool { 
    FirebaseApp.configure()
}

If this doesn't work try sending some data to firebase like so:

Analytics.logEvent("This is a test", parameters: [
            "Test1": "tester",
            "Test2": "tester"
            ])

This will send analytics data to Firebase

The actual trick here is to use latest version of the pod(s).

Firebase forces you to use the latest version of the pods in order to complete the final step check.

Let's say you had pods with specific versions in Podfile:

pod 'Firebase/Analytics', '= 6.27.0'
pod 'Firebase/Crashlytics', '= 6.27.0'

Remove explicit versions

pod 'Firebase/Analytics'
pod 'Firebase/Crashlytics'

Remove app from device / simulator. Rebuild, run app. Check back on Firebase site.

After this, you can set any version in Podfile, execute pod install.

I had the same issue. I was using Firebase/Analytics 6.11.0 and when i changed to 6.8.2 fixed the problem

Google Release Version 6.12 on November 5th, 2019. I would recommend update to the latest version.