Duplication of transactions - many times higher values

If the transaction values are many times higher in GA4, there is most likely duplication - orders sent to GA4 many times.

If orders are doubled in GA, it means that something else is sending orders. Please check if the store is using other modules that can do this - you need to disable or modify them. Sometimes it happens that the code that sends orders to GA is placed directly in the template - you need to remove this code. It can also be, for example, transferring transactions from GTM to GA4. All other codes sending orders should be disabled so that our module can work properly.

According to the documentation, transactions will not be duplicated if they contain the same order ID and user ID - https://support.google.com/analytics/answer/12313109?hl=en
PShowConversion module sends transaction_id for purchase event, and user_id in all events. Both for events sent by Measurement Protocol and those sent by Google Tag (gtag).

You should also analyze and choose how transactions are to be delivered to GA4 (since multiple sources of transactions can lead to duplication):
1. via Measurement Protocol - the order will be shipped even if the customer does not return to the order confirmation page; the module saves the shipment information and will not send this order multiple times
2. via Google Tag dataLayer, with the `purchase` event - standard action, but if the customer does not return to the order confirmation page or has tracking blocking in the browser, the order will not go to GA4
3. via GTM - the module will send the purchase event to GTM and from there it will be forwarded to GA4, the disadvantages are the same as in pt. 2