If you were to give an outright "No" to a customer's question, that would diminish the value of your service. Of course, you won't always know the answers, but it's about how you manage the "No."
Don’t offer a bland "I'm sorry, I don't know."
Imagine saying this, and you have the customer give you a blank stare. If you don't offer to be helpful to a customer in need, that only frustrates them more. Thus, making your job harder.
Instead, focus on alternatives:
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