Error: Rule “includeSku” not found. Reconfigure Advanced Commands to resolve.

Hi, we’re using the add-on to include / exclude SKUs from https://www.exportfeed.com/documentation/include-or-exclude-skus/ but we’re getting:

Error: Rule “includeSku” not found. Reconfigure Advanced Commands to resolve.

Can you advise what we’re doing wrong? We’re running on WP multisite, with both plugins active. The rule has been added as
rule includeSku()

with kind regards, Edith