How to test the triggering of the purchase event (order) on my site?

To test the triggering of the order event on your site (the "Purchase" event):

Start by installing the Google Chrome extension "Datalayer Checker" in your Chrome browser.
Then, go to your site and place a test order.
Once on the order confirmation page, open the "Datalayer Checker" extension (which you will find at the top right of your browser, in the list of your extensions) and check that the "purchase" event appears, as below:

If it does not appear :

You may have an ad blocker. If so, disable it and start over. Keep in mind that because ad blockers and cookie blockers in your customers' browsers prevent tags like Google Analytics from working, you will never have 100% of the conversion data sent to Google Analytics. This is why you will always have a lower number of conversions in Google Analytics than the actual number of orders on your site. Where there can be a problem is if you don't see any orders coming up in Google Analytics. In this case, it could be due to one of the two reasons below.

This may be due to a Javascript error on the order confirmation page
Finally, it can come from the payment method used which does not redirect to the order confirmation page. This is where the tracking tag is placed. If the order confirmation page is not displayed, then the tag cannot be triggered.

In the latter two cases, ask your technical contact to correct the problem.