Why is the Material Service Activity Code not appearing in the Material section LOV on Debrief Page?

EBS 12.2.6

Setup Performed:

1. Created Service Activities for Labor (L), Expense (E), and Material (M)
2. Enabled checkboxes for OM Interface, Create Charge, and Flag Update
3. Mapped each SAC to the appropriate Billing Type, Operating Unit, and Order Type
4. Added the SACs under the relevant Service Business Process for Field Service

Result:
In the Debrief HTML page, the SACs appear correctly under the Labor and Expense sections. However, the Material SAC is not appearing in the Material section LOV.

I'm wondering if there’s any additional setup or dependency required specifically for Material billing type SACs to appear in the Debrief Material section.