When faced with a situation where I don't know the answer to a customer's question, my first priority is to maintain transparency and honesty. I would let the customer know that I'm not certain about the answer, but will find out for them as quickly as possible. I would then consult available resources such as internal knowledge bases, company guidelines, or reach out to colleagues who might have the necessary expertise. Once I've gathered the correct information, I would promptly get back to the customer with a clear and concise response, ensuring their query had been fully addressed. This approach demonstrates both professionalism and commitment to providing accurate information while maintaining a positive customer experience.