Your LoginWithGooglePlusSDK and your presented sample are deprecated

Hi @Nestech_Co3 !

This method expects that you will pass access token, not the ID token.
You should extract auth code from GoogleSignInAccount using getServerAuthCode() method ( GoogleSignInAccount  |  Google Play services  |  Google Developers ) and then echange it using this method AuthorizationCodeFlow (google-oauth-java-client 1.32.1)

More information about auth flow with Google you can get by this link Using OAuth 2.0 with the Google API Client Library for Java

Regards, Andriy