You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: My sister blessed with a baby, so I need to go from IAH to DTW. Can you make a reservation for me?

ASSISTANT: Sure, I can make it for you. Kindly share your travelling dates please?

USER: Thank you. My travel dates are 12/26 and 12/28.

ASSISTANT: Ok, can I know your name?

USER: I am Michael Carter.

ASSISTANT: Carter, sorry to inform you there is no flight available on your provided dates.

USER: It's ok. Thanks for checking.

ASSISTANT: You are welcome.