When I submit form page is redirecting back in laravel 5.5

I have a form and inputs are inside loop. Each inputs are validating using Laravel validation array method. At present I am submitted name as guest[{{ $cart->_id }}][sleeps] guest[{{ $cart->_id }}][comments].

Validation is working fine for each input. But data is not submitted in to controller page. After submit the form, page is redirect back. I am getting http 302 status.

If I change name like name="sleeps[]" and name="comments[]" the data is posting in to controller. Any help would be appreciated.

routes.php

Route::post('/cart/store', 'CartController@store')->name('cart.store');

cart.blade.php

<form action="{{ route('cart.store') }}" method="post">

 {{ csrf_field() }}

<div class="panel panel-default text-left panel-booking1 panel-default-booking1">
    @forelse($carts as $key => $cart)
    <div class="col-sm-4 col-sm-4-booking1 form-group {{ $errors->has('guest.*.sleeps') ? ' has-error' : '' }}">
        <label>Sleep(s)</label>

        <select class="form-control form-control-booking1 jsBookCalSleep"  name="guest[{{ $cart->_id }}][sleeps]">
        <option value="">Choose Sleep(s)</option>
        @for($i = 1; $i <= 30; $i++)
           <option value="{{ $i }}" @if($i == $cart->sleeps) selected @endif>{{ $i }}</option>
        @endfor
        </select>

        @if ($errors->has('guest.*.sleeps'))
             <span class="help-block"><strong>{{ $errors->first('guest.*.sleeps') }}</strong></span>
        @endif
    </div> 

    <div class="col-sm-4 col-sm-4-f-booking1 comment-booking1 col-sm-4-booking1">
       <div class="form-group {{ $errors->has($inputComments) ? ' has-error' : '' }}">
         <textarea id="comments_{{ $cart->_id }}" name="guest[{{ $cart->_id }}][comments]" class="form-control" rows="3" maxlength="300" placeholder="Comment...">{{ old($inputComments) }}</textarea>

         @if ($errors->has($inputComments))
           <span class="help-block"><strong>{{ $errors->first($inputComments) }}</strong></span>
         @endif

      </div>
    </div> 

    @empty
      <p>No bookings in your cart</p>
    @endforelse

<div>
<div id="btn-ground-2-booking1">
    <button type="submit" class="btn btn-default-booking1 btn-default btn-sm btn-details btn-details-booking1"><span class="glyphicon glyphicon-credit-card" style="font-size: 14px;" aria-hidden="true"></span> Payment</button>
</div>
</div>
</form>

CartRequest.php

public function rules()
    {
        return [
            'guest.*.sleeps'     => 'required|not_in:0',
            'guest.*.comments'   => 'max:300',
        ];
    }

CartController.php

public function store(CartRequest $request)
    {
        dd($request->all());
    }

Chrome Console

General
Request URL: https://frontend.test/cart/store
Request Method: POST
Status Code: 302 
Remote Address: 192.168.10.10:443
Referrer Policy: no-referrer-when-downgrade

Request Header
:authority: frontend.test
:method: POST
:path: /cart/store
:scheme: https

Form Data
_token: SBpj6Cf87TyDmUeqM1N8MoREmBwG7MdzCsPR9BHr
guest[5ac5e2e09a892042bb7b2d59][sleeps]: 1
guest[5ac5e2e09a892042bb7b2d59][comments]: 
guest[5ac5e2f49a89205a311248ef][sleeps]: 1
guest[5ac5e2f49a89205a311248ef][comments]: