Incorrect Last Order Date sent to ActiveCampaign CRM

[JWMI]

We use ActiveCampaign as CRM and it is integrated with Shopify. The "last order date" is an extremely important field for our automations and reporting. Over the past few days, there are a bunch of customers that appear to have a new order because their last order date says so, but this is not true and their last order dates were months or years ago. I have tested updating a field in shopify contact to see if it would pass refreshed information on to ActiveCampaign as it usually does, but unfortunately, it didn't do anything for the incorrect order date (did update the note/tags/etc as expected). When I look at the Shopify Orders Widget in ActiveCampaign, I can see something labeled "legacy connection" and there is a numerical digit there (for example "6"). and when I look at the details listed for an order in question there, it also shows the order creation date - the real order date, along with an order modified date - which is the same date that has been inserted now as the incorrect last order date. 

1. What is the problem?

2. Most important - How do I correct it?