var newData = {
        Username: this.username.value,
        Password: this.password.value,
        User_Group: this.User_Group.value,
    }

      var email = this.state.edit_details[0];




    firebase.database().ref("/Cred_Details_Of_Users").orderByChild("Email_Address").equalTo(email).update(newData);

var query = firebase.database().ref("/Cred_Details_Of_Users").orderByChild("Email_Address").equalTo(email);
query.on("child_added", function(snapshot) {
    snapshot.ref.update(newData);
})