We are using a private API, we have had a couple of incidents where within the request from the API and response from Shopify the decimal place in the price is confusing it for an integer of a thousand separator. For example a £629.00 jacket has sold for £629,000.00, see screenshots below
From what we are able to see the item with value 652.654 is the only one with three decimal numbers, with this the dot is being processed has thousands separator the other ones have four numbers, that is preventing this mismatch for the other values.
From an integrations point of view, we are pushing the values shared by the back offices without any change.
Is there any configuration on your Shopify store that can affect the way the values are being matched?.