mews/captcha doesn't accept right answer (always need to reload the captcha to make it works)

Question

I need to use math image captcha and mews/captcha is the best one I've seen so I implemented it. But I always need to reload the captcha first to login properly. Is this a bug and how to fix this without modifying vendor directory?

login.blade.php

<div class="form-group row">
    <label for="captcha" class="col-md-3 col-form-label text-md-right">Captcha</label>
    <div class="col-md-6 captcha">
        <span>{!! captcha_img() !!}</span>
        <button type="button" class="btn btn-danger" class="reload" id="reload">
        &#x21bb;
        </button>
    </div>
</div>
<div class="form-group row">
    <label for="captcha" class="col-md-3 col-form-label text-md-right">Enter Captcha</label>
    <div class="col-md-6">
        <input id="captcha" type="text" class="form-control" placeholder="Enter Captcha" name="captcha">
    </div>
</div>
<div class="form-group account-btn text-center m-t-10">
    <div class="col-xs-12">
        <button class="btn w-lg btn-primary waves-effect waves-light" type="submit">Sign In</button>
    </div>
</div>

<script type="text/javascript">
$('#reload').click(function () {
    $.ajax({
        type: 'GET',
        url: 'reload-captcha',
        success: function (data) {
            $(".captcha span").html(data.captcha);
        }
    });
});
</script>

LoginController.php

public function reloadCaptcha()
{
    return response()->json(['captcha'=> captcha_img()]);
}

public function loginAction(Request $request){

    $validator = \Validator::make($request->all(), [
        'email' => 'required',
        'password' => 'required',
        'captcha' => 'required|captcha',
    ]);
    if ($validator->fails()){
        $data = $validator->getMessageBag()->toArray();
        return Tools::jsonResponse('error', 'Mohon perbaiki data pada formulir yang diberikan', $data);
    } else {