Causes and Resolution:
1). This error arises when certain item data is absent in the order, necessitating a re-download of the order to resolve the issue.
Follow the instructions mentioned in this article: How to Re-download Orders into Webgility Online.
2). In certain instances, the item or customer data may have been updated in QuickBooks, prompting the need to re-download the data from scratch and save the settings.
Refer to this article for step-by-step instructions on performing this process.