Shopify: Qty field is not an integer
A SKU within the product is failing to be updated in the back-end of Shopify.
shopify
This error is caused by a mismatch between the warehouse used for the Shopify channel and the warehouse assigned to a particular SKU. When a particular SKU does not pull stock from the warehouse assigned to the Shopify channel (but the product is set to sync to Shopify) it will create an error as Stock2Shop attempts to sync a value that does not exist.
Check that the SKU is in the warehouse assigned to the Shopify Channel.