How to add a supplier item association to an Item?

Summary:

How to add the item supplier number association to an item?

Content (required):

Hello,

I am trying to add a supplier item association. I am able to add the supplier, but I can't add a supplier item. Am I missing a setup? What is required to fill this field?

Thank you,

Eolie

Version (include the version you are using, if applicable):

21B

Code Snippet (add any code snippets that support your topic, if applicable):