field not editable

The Total Price Change % (Total_Price_Change__c) field is configured as a Percent field and its Edit Access is disabled in the Profile/Permission Set, and it is also set as Read-Only on the Lightning Record Page. However, the field is still appearing as editable in the Quote Line Item record. What could be causing this behavior, and is there any other configuration (such as Page Layout, Dynamic Forms, custom component, Flow, Quick Action, or managed package) that could be overriding the field-level read-only setting?