WC Products Per Page

My theme doesn’t allow the option to adjust products per page via WPAdmin>Customize

I add this code to my functions page and it seems to be working, except it doesn’t work on the 1st page of my shop. Any suggestions?

/**
 * Change number of products that are displayed per page (shop page)
 */
add_filter( 'loop_shop_per_page', 'new_loop_shop_per_page', 20 );

function new_loop_shop_per_page( $cols ) {
  // $cols contains the current number of products per page based on the value stored on Options –> Reading
  // Return the number of products you wanna show per page.
  $cols = 9;
  return $cols;
}

The page I need help with: [log in to see the link]