Hello p moseng,

We are here to help you. 

The recommended solution provided in the previous answer is to set the Preferred delivery method to None. If the customer is already in the correct setup, let's run the other solutions to fix this issue. 

First solution is to make sure the QuickBooks is on its updated release version. In QuickBooks, click on the Help menu then choose Update QuickBooks. By updating QuickBooks, it helps to install new product solutions for issues like this one.

Second one is to repair QuickBooks. Please see this article for the detailed steps: Repair or reinstall Microsoft .NET Framework. It restore QuickBooks' default functionality and remove unwanted behavior. 

Go ahead and generate the customer statement again.

Let us know if you need anything else.