WooCommerce saved amount

Hello, I would like to show the saved amount on sale products. Here is the code that I’m using, but my currency is now showing, only the saved amount. Any ideas how to fix it? Thanks in advance!

function usteda_popust() {

global $product;

if( $product->is_type('simple') || $product->is_type('external') || $product->is_type('grouped') ) {

$regular_price = get_post_meta( $product->get_id(), '_regular_price', true );
$sale_price = get_post_meta( $product->get_id(), '_sale_price', true );

if( !empty($sale_price) ) {

$amount_saved = $regular_price - $sale_price;
$currency_symbol = get_woocommerce_currency_symbol();
?>
<p style="font-size:18px;color:red;">U?teda: <?php echo number_format($amount_saved,2, ',', '') ?></p>
<?php
}
}
}

add_action( 'woocommerce_single_product_summary', 'usteda_popust', 11 );

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