laravel my update function is not updating all data

I want to update the data from two table users and traveller_Infos. But only the user table is updating. this is my controllers

public function update($id,Request $request){
$user_id = auth()->user()->id;
$user = User::find($user_id);

$travel=new TravellerInfo;
$cus_info= $travel->where('travel_id',$user_id)->first();
$this->validate($request, [
        'name' => 'required', //|string|max:255',
        'email' => 'required', //|string|email|max:255|unique:users,
        'password' => 'required',

         'num_adults' => 'required',

]);
$user->name = $request->input('name');
$user->email = $request->input('email');
$user->password = $request->input('password');
$user->save();
$cus_info->num_adults = $request->input('num_adults');
$cus_info ->save();
return redirect()->route('home');

}

via Chebli Mohamed