Worked on enhancing billing data integrity within the microsoft/BCApps repository by addressing a critical issue related to subscription item deletion. Developed an event-driven safeguard in AL, leveraging backend development and unit testing skills to prevent the removal of subscription items when a contract invoice is deleted. This approach involved code-unit level changes to Contracts Item Management, ensuring that items created from catalog entries remain intact and ongoing subscriptions are not disrupted. The solution resolved a key bug, reducing the risk of cascading deletions and revenue loss, and contributed to more reliable and consistent subscription billing workflows across the application.