Invalid Product

Hi,

I found that Xeroom was adding new inventory products to Xero instead of matching with the existing inventory products set up in xero. So I added SKU’s to all products in WooCommerce that match the Product ID in Xero. However, now when I checkout, I get an “invalid product” error. There is nothing in the debug page for Xeroom. But if I deactivate the Xeroom plugin, the sale goes through checkout in WooCommerce fine. And if I activate the plugin, but remove the SKU, it goes through fine. So for some reason, adding the SKU means I get an “invalid product” error when clicking on the PayPal payment button in the WooCommerce checkout?