woocommerce_quantity_input_step not working properly

Hi Team,

I’m using below code to change quantity steps based on custom attribute on product page.

// Add min value to the quantity field (default = 1)
add_filter('woocommerce_quantity_input_min', 'ysn_min_decimal');
function ysn_min_decimal($val){
    return 1;
}

// Removes the WooCommerce filter, that is validating the quantity to be an int
remove_filter('woocommerce_stock_amount', 'intval');

// Add a filter, that validates the quantity to be a float
add_filter('woocommerce_stock_amount', 'floatval');

add_filter('woocommerce_quantity_input_step', 'ysn_quantity_input_step', 10, 2);
function ysn_quantity_input_step($step, $product){
    $product_id = $product->id;
    $meta = get_post_meta($product_id);
    $sku_data = array();
    if(isset($meta['_product_attributes'][0])){
        $sku_data = unserialize($meta['_product_attributes'][0]);
    }
    $sku_unit_value = "";
    if(isset($sku_data['unit'])){
        $sku_unit_value = $sku_data['unit']['value'];
    }
    if(isset($sku_data['category'])){
        $sku_unit_value = $sku_data['category']['value'];
    }
    if(strtolower($sku_unit_value) == "kg"){
        $step = 0.25;
    }
    return $step;
}

But, it doesn’t work for me. Can you please help me on this.

Thank you!
Yeshan Perera