AME : Error Ensure a rule has conditions based on atmost one non-header item class attribute

Hello,

I am trying to make a rule in AME to have FYI notifications (Approved PO) be sent to the managers, but this notifications will be just for the PO from a certain group of items categories, certain OUs and just for the branches the managers are in charge.

The condition I created is as follows for the first group of branches:

The COA Branch Condition, was created by me in order to get the branches...

But when I apply it, I get the Error Ensure a rule has conditions based on atmost one non-header item class attribute

I have been looking for this error online and metalink, no results... Please help me to find the way to create the rule to meet these conditions.