Code issue on product pages

Hi

I used this code on the functions.php to show “You save(x%)” message under the price in every product page, but in some product pages with just 1 option color doesn’t work like this one:  https://www.runayaq.com/producto/runayaq-mujer-polo-negritos-de-huanuco/ and in other products with 2 options of color, it appears like this :

Code used:

add_action( 'woocommerce_single_product_summary', 'display_savings_percentage', 12 ); 

function display_savings_percentage() { 
global $product;     

$regular_price = $product->get_regular_price(); 
$sale_price = $product->get_sale_price();          

if ( ! $regular_price || ! $sale_price ) {         
return;     
}     

if ( $product->is_type( 'variable' ) ) {         
$min_price = $product->get_variation_regular_price( 'min', true );         $max_price = $product->get_variation_regular_price( 'max', true );         $min_sale_price = $product->get_variation_sale_price( 'min', true );         $max_sale_price = $product->get_variation_sale_price( 'max', true );         

if ( ! $min_price || ! $max_price || ! $min_sale_price || ! $max_sale_price ) {
return;         
}         

$regular_price = ( $min_price === $max_price ) ? $min_price : $min_price . ' - ' . $max_price;
$sale_price = ( $min_sale_price === $max_sale_price ) ? $min_sale_price : $min_sale_price . ' - ' . $max_sale_price;     
}     

$savings_percentage = round( ( $regular_price - $sale_price ) / $regular_price * 100 ); 
echo '<p class="savings-percentage">You save ' . $savings_percentage . '%</p>'; }

how to fix that ?

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