You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I do for you?

USER: I am planning to visit a Houston Museum of Natural Science in HOU from DEN. Can you find a ticket for me?

ASSISTANT: Of course, I will check the available flights. Can you please provide me the departure date and return date?

USER: Sure, I am planning to travel for two days that is 01/17 to 01/19.

ASSISTANT: Ok, in the mean while can you tell me your name?

USER: Yes, I am Mark Davis.

ASSISTANT: Ok Mark, please wait a minute, I will revert you.

USER: Ok, sure.

ASSISTANT: Sorry to inform you, there are no flights for you on your planned dates.

USER: Ok, no problem.

ASSISTANT: Do you want me to help anything else?

USER: No, thank you for your information.

ASSISTANT: Our pleasure to help you.