Duplicated conversion counting in GA when thankyou page is loaded again

Question

I received 2 snippets from google support to connect my website with ads/analytics. It works fine (value, etc), except duplicates/multiplied values. My conversion (purchase) is duplicated every time when customer visit order confirmation link (like from email). 4 links clicked = transaction multipied by 4. How can I get rid off that?

Script 1:

    function ads_purchase_tracking($order_id){
       $order = new WC_Order($order_id);
       $currency = $order->get_order_currency();
       $total = $order->get_total(); 
       $cart_value = number_format( (float) $order->get_total() - $order->get_total_tax() - $order->get_total_shipping(), wc_get_price_decimals(), '.', '' ); ?>
        <script>
         gtag('event', 'conversion', {
        'send_to': 'AW-XXXXXXXX/XXXXXXXXXXXXXXXXXXXXXX',
        'value': <?php echo $cart_value ?>,
        'currency': '<?php echo $currency ?>',
        'transaction_id': '<?php echo $order_id ?>'
  });
</script>

Script 2:

<?php
$order_id = $order->get_order_number();
$total = $order->get_total();
$order_shipping_total = $order->get_total_shipping(); 
$order1 = new WC_Order( $order_id );
$items = $order1->get_items();
?>

<script type="text/javascript">
    gtag('event', 'purchase', {
          'transaction_id': '<?php echo $order_id ?>',
          'affiliation': '<?php echo $order->get_payment_method() ?>',
          'value': <?php echo $total ?>,
          'shipping': <?php echo $order_shipping_total ?>,
          'tax': <?php echo $order->get_total_tax() ?>,
          'currency': '<?php echo $order->get_currency() ?>',
          'items' : [
        <?php if(count($items) > 0){ ?>
        <?php foreach ( $items as $item ) { ?>
            <?php $product = $order->get_product_from_item( $item ); ?>
                {
                'id': '<?php echo $product->get_id() ?>',
                'name': '<?php echo $product->get_name()?>',
                'category': '<?php echo $product->get_categories() ?>',
                'price': <?php echo $order->get_item_total( $item ) ?>,
                'quantity': <?php echo $item['qty'] ?>
                },
        <?php } ?>
    <?php } ?>
                    ]
    }); 
</script>
<?php }
'''