You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hi. How may I help you?

USER: Joseph Hall here. Reserve a flight ticket for me that is from IAH to EWR.

ASSISTANT: Sure, I am here to help you. Could you please share your travelling dates?

USER: Sure, my preferred dates of trip are 12/01 and 12/03.

ASSISTANT: Please wait for a moment.

USER: Ok.

ASSISTANT: Sorry, no flight is available for you.

USER: No problem, thank you.

ASSISTANT: Thank you for choosing us, have a nice day.