Aria Operations 8.x
If the properties are not enabled in the policy assigned to the vLAN objects in question, then those properties will not be visible under the Metrics section for the vLAN IDs
Edit the assigned policy for the objects and Activate the required properties from the policies. Once the required properties are activated in the policy assigned to the VLAN, they should appear under the Metrics tab and the values will be present in the Network Configuration Dashboard for Port Groups.
Refer Policies documentation for Aria Operations: Policies, Policy Decisions and Objectives, Assigning Policies