Item rule is not working

Summary:

Hi guys, We´ve created a rule in item using "Manage item Rule set" to generate a validation rule to permit only uppercase letters and numbers in the "Item Number" at creation moment, but it is not working.

I´m not sure if something is missing. Is it necesarry to link the rule in item class screen?

as I tried that but rule list of values is grayed out in item class "Producto Terminado" or its parent.

Otehrwise offering "Product Rule" is tagged.

SR is created, but they sent me here.

We appreciate any help.

Thanks!

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