SCIM 2 Connector - Reading extension enterprise schema

I have configured a SCIM 2.0 connector in IdentityIQ, all working fine, except It only works with the ‘base’ schema - urn:ietf:params:scim:schemas:core:2.0:User

How do I add in the extended schema - urn:ietf:params:scim:schemas:extension:enterprise:2.0:User - so I can get the employeeNumber value?

Attachment are response from /ResourceTypes api and /Schema API.
ResourceType.txt (1.2 KB)
Schema.txt (47.9 KB)

Appreciate any assistance