Login with google issue

Hello,

I’m already using login with google feature on my website and it’s working well.

Now come to the issue. I have created my own android app which is based on webview . Issue on the app is google sign in not working but facebook sign in working.

But want to google sign on in my aap too. I’m getting an error like this.

Authorisation Error
Error 403: disallowed_useragent
Google can’t sign you in safely inside this app. You can use Google sign-in by visiting this app’s website in a browser like Safari or Chrome

The page I need help with: [log in to see the link]