Mismatch token error in laravel

My login form works correctly:

<form action="{{route('autenticacao.logar')}}" method="post">
    {{csrf_field()}}
    <input type="text" name="cpf" class="form-control" placeholder="CPF" style="border-radius:10px; border-color:blue;" />
    <br/>
    <input type="password" name="senha" class="form-control" placeholder="senha" style="border-radius:10px; border-color:blue;" />
    <br/>
    <input type="submit" class="btn btn-primary btn-block btn-flat" value="Entrar" />
</form>

However, if I log off:

public function logout(){
    Auth::logout();
    Session::flush();

    return view('autenticacao.login');
}

When I try to re-login, I get an error:

  

TokenMismatchException   in VerifyCsrfToken.php line 68

But if I refresh the page it works normally, however it's annoying for the user to have to refresh the page whenever he wants to sign in again.

What can it be?