could not redirect page when no session

//helper function 

function check_session_set() {
   
    $session      = \Config\Services:ession();
    if( $session->has( 'id' ) ) {}
    else {
    echo 'test';
    redirect()->to('public');
    }
    return true;
}



//basecontroller

    public function initController(\CodeIgniter\HTTP\RequestInterface $request,       \CodeIgniter\HTTP\ResponseInterface $response, \Psr\Log\LoggerInterface $logger)
    {

    parent::initController($request, $response, $logger);
    helper(['common_helper','form', 'file']);
    $validation = \Config\Services::validation();
    $this->session = \Config\Services:ession();

        check_session_set();

}

when i logout and click back button the page did not redirect to login page.but echo 'test' message shows.
is there redirect work in helper function