Unable to Key In Billing Plan in Sales Order (SO)

Symptoms

• When creating a new Sales Order, after selecting a billing plan, the billing plan fields under item details could not be edited.
• Item-level billing plan remained locked/uneditable.

Root Cause

HeadBillPlan (Header Billing Plan) was enabled, which overrides item-level billing plan maintenance and prevents edits.

Resolution

1. Untick HeadBillPlan.
2. Navigate to another tab.
3. Return to the Billing Plan tab to trigger a UI refresh and enable item-level editing.

Prevention

• Ensure HeadBillPlan is unticked before maintaining item-level billing plans.