PiracyChecker fails to check whether the app is installed from Google Play Store

I'm using 'com.github.javiersantos:PiracyChecker:1.2.3' because my app is not yet integrates AndroidX.

I have numerous reports from user reviews in my app's Google Play page that they have installed the app from the Google Play Store, yet they getting the piracy warning message.

Here are some examples:

Also got a user report via email:

My app have 4k reviews and only 3 of them are like this, but I don't know the exact user count because there could be users who don't comment about this issue.

What is going on?

I use it like this:

    public static void showPiracyActivityIfNeeded(final Activity activity) {
    if (!BuildConfig.DEBUG) {
        //Releaseb build, piracy check.
        new PiracyChecker(activity)
                .enableInstallerId(InstallerID.GOOGLE_PLAY)
                .callback(new PiracyCheckerCallback() {
                    @Override
                    public void allow() {
                    }

                    @Override
                    public void dontAllow(@NonNull PiracyCheckerError piracyCheckerError, @Nullable PirateApp pirateApp) {
                        Intent intent = new Intent(activity, PiracyWarningActivity.class);
                        activity.startActivity(intent);
                        activity.finish();
                    }
                })
                .start();
    }
}

Thanks in advance.

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