Navigation Arrows Snippet Acting Really Strange

Hi Guys, I use this snippet to display arrows for navigation between product photos and it works 100% on a computer.
`add_filter( ‘woocommerce_single_product_carousel_options’, ‘sf_update_woo_flexslider_options’ );

function sf_update_woo_flexslider_options( $options ) {

$options[‘directionNav’] = true;

return $options;
}`

However, when I use a smartphone it only works properly on 7 out of 13 products.
For products on which the snippet does not work properly, it is necessary to wait about 30 seconds on the product page and only then will the arrows start working.
I use WooCommerce with Storefront theme.
I will be grateful for any suggestions of how could I fix it.

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