Response: My first step would be to engage with the relevant stakeholders to clarify the ambiguous and incomplete data. This could involve setting up meetings or workshops to gather more detailed requirements and ensure that everyone is aligned on the business objectives. I would also review any existing documentation or historical data to fill in gaps and ensure that I have a comprehensive understanding of the requirement. Once I have the necessary information, I would document it clearly and validate it with stakeholders before proceeding with the next steps in the product development process.