Line Item Quantity Must Be Greater Than 0
Shopify no longer allows you to import orders with a line item quantity less than 1. If your import file does not have a quantity field or if it's value is less than 1 you must update the quantity field to a value that is greater than or equal to 1. To read Shopify's announcement about this validation change click here.
You also can not set the quantity value to a decimal, the value must be a whole number.
App: EZ Importer