While using a parameterized lookup that works as expected on the Classic UX, the Modern UX does not return any values, and you observe an error like:
One or more parameters 'param_xyz' are not API-enabled. You may see unexpected results.
If the parameterized lookup is based on NSQL like this:
[...]
WHERE @FILTER@
AND (@WHERE:PARAM:USER_DEF:STRING:GARMENT@ IS NULL OR @WHERE:PARAM:USER_DEF:STRING:GARMENT@ = garment.name)
[...]
the error displayed should be like this:
One or more parameters 'param_garment' are not API-enabled. You may see unexpected results.
Release : 15.9.3
Component : Clarity Studio
The attribute that is mapped to the lookup parameter does not have an API alias, so it is not enabled for the Modern UX.
Go to Administration > Studio > Objects > [object] > Attributes > [parameterized lookup attribute].
In the Lookup Parameter Mappings section, look for the parameter lookup (following the previous example, "garment") and check the Object Attribute ID that is selected.
Find that attribute in the object attributes list and ensure that it has an API Attribute ID.