Hi there. I am trying to add multiple line items (product and shipping) to a Wave invoice from Shopify and am getting the following error
Failed to create an invoice in Wave
Cannot convert undefined or null to object
A possible problem as mentioned in another post is that some data could be custom, but all my entries are data fields. Additionally, when I enter each line item by its self, there is no error and an invoice is generated in Wave, but together throw an error. I have tested everything I can think of! Please see the attached screen shot.
