Out of stock class missing

Hi, I have just recently updating your plugin after 2 years and the buttons no longer have a cross through them and the out of stock class “ic_out_of_stock” is missing. I have done a video showing my staging site with the old plugin version and the new website.

I have also added the following functions which were recommended in the comments as a fix but they do not help

add_filter( ‘woo_variation_swatches_global_ajax_variation_threshold_max’, ‘woo_variation_swatches_global_ajax_variation_threshold_max_edit’, 10, 2 );
function woo_variation_swatches_global_ajax_variation_threshold_max_edit( $size, $product ){
return 700;
}

function custom_wc_ajax_variation_threshold( $qty, $product ) {
return 500;
}

add_filter( ‘woocommerce_ajax_variation_threshold’, ‘custom_wc_ajax_variation_threshold’, 10, 2 );