To address the challenges, we built a comprehensive data store that integrated customer, product, and transaction data to identify patterns and systemic issues. The system was designed to recalculate fees and interest charges and compare them with what had actually been charged. This analysis uncovered overcharging and allowed for the development of cost-effective remediation strategies, taking into account the time value of money. Automated systems were implemented to accurately calculate the correct customer outcomes, ensuring a fair and efficient process for all impacted customers.