Yes as I say, I suspect we will have to wait for the next problem to occur, so that we have the debug log. Without the debug log and with the fact that product changes are not tracked (WP only keeps revisions for posts and pages) it is hard to establish the exact sequence of events and triggers, and to link them to the appropriate orders and products.
I have assumed that the ‘Signup to Marketing’ setting is ‘No’. Please let me know if this was incorrect (or if you have entered a ‘Marketing Form ID’);
With the ‘Add/Update Contact’ option checked the sync with ActiveCampaign should happen when an order is created with a status of ‘processing’ (usually at the point of customer checkout). The sync event is triggered by order status changes. So it is hard to see how a sync (to create a contact or add/remove tags) could happen without it being triggered by an order status change.
If there were no orders for these contacts then I’m struggling to explain what happened. The plugin must have an order from which it will get the email address to look up the contact on ActiveCampaign. The email address is the all important link. I can speculate that orders could have been deleted, or emails addresses changed on the order, but it is just guessing. The debug log would be the only definitive record since it will show the order ID that triggered the sync, the order status at the time, the timing to the second, the AC ID of the contact that matched the email on the order, and the exact tags added.
There will be some explanation! There always is but I’m not there yet.
Only last thing I can think of is to ask if you have a testing or staging environment? Testing orders or manually changing orders status on a testing environment will trigger a sync to ActiveCampaign. Long shot but worth asking I guess. Taking that point one step further I guess it would also be possible to mistakenly use the same API key if you had another web site that used the plugin but I’m clutching at straws here.
Let me know if any ideas come to mind based on what I’ve said above, otherwise I suggest we wait for the debug log. Check that everything that has been logged since you enabled it is as you would expect and then wait for a similar fault to occur.
Best regards,
Matt