Simply replace the wp_pagenavi(); by
if(function_exists('wp_pagenavi'))
{
wp_pagenavi(array( 'query' => $loop) );
wp_reset_postdata();
}
Simply replace the wp_pagenavi(); by
if(function_exists('wp_pagenavi'))
{
wp_pagenavi(array( 'query' => $loop) );
wp_reset_postdata();
}