I have not found a way to ask this directly to facebook assistance because there is not an email address or chat/phone support. I am testing facebook pixel event trigger on the ads control panel and I found that on every refresh a PageView event is triggered and on the thank you page a Purchase event too. When the ads will be published officially, do facebook automatically recognize someone refresh the page and so will not charge me every time or I have to write some php code to avoid that?
Thank you Juherianto for your reply. My web store is made by woocommerce. And i pay per impressions. How to pay per click?