Oauth 2.0: I can't get profile info from Google "token info endpoint" by using id_token - authentication

Question

I'm trying to get user info (profile,email) from Google by using OAuth 2.0.
But "token info endpoint" did not return profile info even though I set "profile" to scopes.
I followed the doc of Google sign-in for iOS. (https://developers.google.com/identity/sign-in/ios/backend-auth)
I couldn't figure out why this end point doesn't return profile info as I expected.
First I get Token by oauth2.0 (as a test, I got token using Rails)
def gmail
require 'oauth2'
client = OAuth2::Client.new(
'Client-id',
'client-secret',
{
site: 'https://accounts.google.com/',
authorize_url: 'o/oauth2/auth',
}
)
redirect_to client.auth_code.authorize_url(
redirect_uri: 'http://localhost:3000/google_signup',
scope: 'email profile',
)
end
token = client.auth_code.get_token(
params[:code],
redirect_uri: 'http://localhost:3000/gmail_signup',
and I get id_tokenfrom this token.
then, send GET request to "token info endpoint".
"https://www.googleapis.com/oauth2/v3/tokeninfo?id_token=id_token"
but response didn't contain profile info.
{
"azp": "azp",
"aud": "aud",
"sub": "sub",
"email": "email#gmail.com",
"email_verified": "true",
"at_hash": "at_hash",
"exp": "TIMESTAMP",
"iss": "accounts.google.com",
"iat": "iat",
"alg": "alg",
"kid": "kid"
}
The response was supposed to be like this.
{
// These six fields are included in all Google ID Tokens.
"iss": "https://accounts.google.com",
"sub": "110169484474386276334",
"azp": "1008719970978-hb24n2dstb40o45d4feuo2ukqmcc6381.apps.googleusercontent.com",
"aud": "1008719970978-hb24n2dstb40o45d4feuo2ukqmcc6381.apps.googleusercontent.com",
"iat": "1433978353",
"exp": "1433981953",
// These seven fields are only included when the user has granted the "profile" and
// "email" OAuth scopes to the application.
"email": "testuser#gmail.com",
"email_verified": "true",
"name" : "Test User",
"picture": "https://lh4.googleusercontent.com/-kYgzyAWpZzJ/ABCDEFGHI/AAAJKLMNOP/tIXL9Ir44LE/s99-c/photo.jpg",
"given_name": "Test",
"family_name": "User",
"locale": "en"
}