Tier Basis “Extended Amount” LOV Is Blank When Creating Tier-Based Discounts for a Usage Charge.

Tier Basis “Extended Amount” LOV Is Blank When Creating Tier-Based Discounts for a Usage Charge.

I am trying to create tier-based discounts in a rate plan. When I select Extended Amount as the Tier Basis Type, the corresponding Value list of values (LOV) is blank, so I cannot select a value.

Is this expected behavior? If not, could someone please advise what configuration or prerequisite is required to populate the LOV? Could this be related to the rate plan setup, pricing strategy, currency, or product configuration?

Any troubleshooting guidance would be appreciated