Hi Andrew. I'm probably telling you what you already know - but this generally happens when something prevents Sellerdeck Desktop from receiving the callback from PayPal with the payment authorisation. I'm not an expert on that area, but AIUI it could be a network interruption, firewall issue or any one of a number of things. You can check in your PayPal account whether they payment was received, and if necessary add a payment record manually in the Order dialog.
When you say 'again' - did you find out what caused it last time?
You could contact support if the problem persists, but it can be quite hard to diagnose this kind of issue from our side. I'd check whether you, your ISP or your web host (if other than Sellerdeck) have done anything that could block the callbacks.
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