ORDER RULE based on product category

Hi, i have setup an order rule which is working up to a point...

order contains item which is category labelled 'LargeLetter' AND follows these rules will convert to Royal Mail

here is the rule set:

• OrderItemProductCategory DoesNotContain Packet

• TotalItems LessThan 28

• TotalWeight LessThan 0.600

• CourierService Equals Evri Standard

i have setup rules to say OrderItemProductCategory Equals LargeLetter AND DoesNotContain Packet

but im still seing this rule run on orders that contain packet items

so if all items in order contain LargeLetter items then i want this rule to run, if 1 or more items on the order contains Packet i do not want it to change the courier

I have been told the 'OrderItemProductCategory' feature doesnt work...

Case reference number: 27081338

i am using multiple keywords in the ruleset to workaround this issue, but my list will continue to grow and i want to run similar rules based on Product Category.

here is my workaround which is going to keep growing...