add_action('wp_login', array($this, 'knp_aci_login_check'), 1, 2);

public function knp_aci_login_check( $user_login, $user ){

    $contact = $this->request->api_connect(
        'contacts?filters[email]='.$user_login,
        'GET'
    );

    if (wp_remote_retrieve_response_code( $contact ) == 200 ) {

        setcookie( 'ac-status', 'true', 365 * DAY_IN_SECONDS, '/', get_site_url() );

    }

}