Unable to Edit the Quantity or Sales Price of an Opportunity Product

When an Opportunity Product has a schedule, the Quantity and Sales Price fields behave as roll-up summary fields and cannot be edited, including via API.

To modify these values:

• Update or remove the associated product schedule.
• Navigate to the Opportunity Product detail page.
• In the Schedule section, use Edit, Delete, or Re-Establish to adjust the schedule.

If the Schedule related list is not visible:

• Ensure product scheduling is enabled at the org level.
• Verify scheduling is enabled on the Product.
• Confirm the Schedule related list is added to the page layout.