Problem to log in using PHP and Codeigniter

Question

I took an internal system of the company to give maintenance and I do not have much knowledge in PHP. When I log on to the application from the company server I can access it normally. I went up the application in a hosting, however, when trying to log in by entering email and password, what appears is a blank screen, and I can’t log in.

Follow the code for analysis:

View 'login/login':

<form class="form-horizontal" method="POST" action="<?= site_url ("Login/entrar") ?>">
    <input type="hidden" name="_token" value="GFSc0XajfwJeVrp2CzYdftCoZ8tslaOkBfIIbLdc">
    <div class="form-group">                      
        <label for="login" class="col-md-4 control-label">E-Mail</label>
        <div class="col-md-6">
            <input id="email" type="email" class="form-control" name="login" value="" required autofocus>
        </div>
    </div>
    <div class="form-group">
        <label for="senha" class="col-md-4 control-label">Senha</label>
        <div class="col-md-6">
            <input id="password" type="password" class="form-control" name="senha" required>
        </div>
    </div>
    <div class="form-group">
        <div class="col-md-6 col-md-offset-4">                                
        </div>
    </div>
    <div class="form-group">
        <div class="col-md-8 col-md-offset-4">
            <button type="submit" class="btn btn-primary">
                Entrar
            </button>
            <!--a class="btn btn-link" href="http://192.168.31.8/vistarraf/password/reset" disabled=disabled>
                Esqueceu sua senha?
            </a -->
        </div>
    </div>
</form>

Controller 'login':

class Login extends CI_Controller{

    public function index(){}

    public function entrar (){
        $login = $this->input->post("login");
        $senha = md5($this->input->post("senha"));
        $this->db->where("email", $login);
        $this->db->where("password", $senha);
        $query = $this->db->get("users");
        if ($query->num_rows() == 1){
            $this->load->helper('weather_helper');
            $previsao = MostraPrevisao(4956);
            $dados    = array(
                'titulo'    => 'Intranet',
                'tela'      => 'inicio',
                'previsao'  => $previsao
            );
            $this->load->view('home_view', $dados);
        } 
        else {
            $mensagem = "Email e Senha não encontrados"; 
            $dados    = array(
                'msg' => $mensagem,
                'tela'      => 'welcome_message_error'                
            );
            $this->load->view('login_view', $dados);      
        }
    }

}