Hi Mohtashim as all your other pixel events are firing (add to cart, initiate checkout etc) it’s likely that your purchase pixel event is being fired by Shopify. So, if you add a script to fire the purchase pixel as well, it will fire twice. The best solution most likely would be to leave the pixel events to Shopify to avoid duplication.

I have a shopify website – mypoojabox.in in which I have installed this script recommended by you on Checkout but I have noticed that still the no. of conversions are counting twice. Refer below screenshot –

https://uploads.disquscdn.com/images/899422c041c11c84bef1855e4b0b4515429e9dbe9c38532021aad125fcc9b7b4.png?w=800&h=365

Here is the customized script that I have been using on checkout –

{% if first_time_accessed %}

!function(f,b,e,v,n,t,s){if(f.fbq)return;n=f.fbq=function(){n.callMethod?
n.callMethod.apply(n,arguments):n.queue.push(arguments)};if(!f._fbq)f._fbq=n;
n.push=n;n.loaded=!0;n.version=’2.0′;n.queue=[];t=b.createElement(e);t.async=!0;
t.src=v;s=b.getElementsByTagName(e)[0];s.parentNode.insertBefore(t,s)}(window,
document,’script’,’//connect.facebook.net/en_US/fbevents.js’);

fbq(‘init’, ‘294416497709223’);
fbq(‘track’, “PageView”);
fbq(‘track’, ‘Purchase’, {
value: ‘{{ total_price | money_without_currency }}’,
currency: ‘{{ shop.currency }}’,
order_id: ‘{{ order_number }}’,
content_ids: [{% for line in order.line_items %}’shopify_{{ line.product_id }}_{{ line.variant_id }}'{% unless forloop.last == true %}, {% endunless %}{% endfor %}],
content_type: ‘product’,
num_items: ‘{{ item_count }}’
});

{% else %}
{% endif %}

Could you please check once and help me out. Thanks in advance!