React-native google signin gives Developer Error

I am trying Google login using React-native-google-signin plugin but it gives me a Developer_Error.I have done exctly same as mention in its document.here is my code ans steps.

1.Installed react-native-google-signin plugin using npm i react-native-google-signin.2.Then have linked it with react-native link react-native-google-signin3.After that i did setup of build.gradle file as they mention it in the documents.

    ext {        buildToolsVersion = "27.0.3"        minSdkVersion = 16        compileSdkVersion = 27        targetSdkVersion = 26        supportLibVersion = "27.1.1"        googlePlayServicesAuthVersion = "15.0.1"    }    dependencies {        classpath 'com.android.tools.build:gradle:3.1.2'        classpath 'com.google.gms:google-services:3.2.1'    }    allprojects {        repositories {                mavenLocal()                google()                 maven {url "https://maven.google.com"}                jcenter()                maven {                // All of React Native (JS, Obj-C sources, Android binaries) is installed from npm                url "$rootDir/../node_modules/react-native/android"                }                maven {                    url 'https://maven.google.com/'                    name 'Google'                }        }    }

4.Updated android/app/build.gradle,

    dependencies {        implementation 'com.facebook.android:facebook-android-sdk:4.34.0'        implementation project(':react-native-fbsdk')        compile project(':react-native-vector-icons')        compile project(':react-native-fused-location')        compile project(':react-native-fs')        compile project(':react-native-image-resizer')        compile project(':react-native-geocoder')        compile project(':react-native-device-info')        compile project(':react-native-image-picker')        compile fileTree(dir: "libs", include: ["*.jar"])        compile "com.android.support:appcompat-v7:${rootProject.ext.supportLibVersion}"        compile "com.facebook.react:react-native:+"  // From node_modules        implementation project(":react-native-google-signin")        compile (project(':react-native-maps')){            exclude group: "com.google.android.gms"        }        implementation 'com.google.android.gms:play-services-auth:15.0.1'        implementation 'com.google.android.gms:play-services-maps:15.0.1'        implementation 'com.google.android.gms:play-services-location:15.0.1'        implementation 'com.google.android.gms:play-services-base:15.0.1'    }    task copyDownloadableDepsToLibs(type: Copy) {        from configurations.compile        into 'libs'    }    apply plugin: 'com.google.gms.google-services'

5.Then generate SHA1 key using android studion debug.keystore and generate google-services.json file in firebase.

6.Then setting up login.js page like this.

    async componentDidMount() {        this._configureGoogleSignIn();    }    _configureGoogleSignIn() {        GoogleSignin.configure({            webClientId: '775060548127-5nfj43q15l75va9pfav2jettkha7hm2a.apps.googleusercontent.com',// my clientID            offlineAccess: false        });    }    async GoogleSignin() {    try {        await GoogleSignin.hasPlayServices();        const userInfo = await GoogleSignin.signIn();        // this.setState({ userInfo, error: null });        Alert.alert("success:"+ JSON.stringify(userInfo));    } catch (error) {        if (error.code === statusCodes.SIGN_IN_CANCELLED) {            // sign in was cancelled            Alert.alert('cancelled');        } else if (error.code === statusCodes.IN_PROGRESS) {            // operation in progress already            Alert.alert('in progress');        } else if (error.code === statusCodes.PLAY_SERVICES_NOT_AVAILABLE) {            Alert.alert('play services not available or outdated');        } else {            Alert.alert('Something went wrong', error.toString());            this.setState({                error,            });        }    }}

These are my details so please someone help me on this i cannot find the appropriate solution online.and yes my SHA1 and clientID is correct i have cheked it already.