In releases before Magento Plugin version 5.0.2., it can happen that shoppers complete the payment process, are redirected back to the web shop success page and the respective order has not been not created.
This issue is caused by the 3DS process, where in some scenarios the shopper flow is disrupted after completing their payment, for example due to Magento throwing an error. As a result, the order is not placed and created.
In Magento Plugin version 5.0.2. or higher we have changed the order flow to prevent this from occurring. In the new flow the payment is only created after an order is created. Download and upgrade your plugin to version 5.0.2 or higher from GitHub or the Magento Marketplace.