SSO Keycloak as SP GSuite as IDP, invalid request error


I set a SAML app in GSuite and want to sign in Keycloak using Google credentials(Keycloak as SP, GSuite as IDP), but I get the error message: Invalid request.

[org.keycloak.event] (default task-23) type=identity_provider_login_error, realmid=demo, clientid=null, ipaddress=xxxx, error=invalidrequestmessage

Can anybody tell me how to solve the problem? Thanks so much.