I don use the item number field. Why is ZonaCart showing an item number on the order form?
ZonaCart uses the item number to prevent users from creating multiple lines for the same item. Multiple lines of the same item will create confusion for you and your customer (your customer should increase the order quantity for the item instead) Because ZonaCart requires this information, it will create a random number if no item number is present. To use ZonaCart as designed, make sure all your catalog items have a unique item number!