You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you for the day?

USER: I am planning to attend music concert at DEN, can you please help me with booking a flight ticket from IAH?

ASSISTANT: Sure, may I know your journey dates?

USER: Sure, I would like to take off on July 21 and return on July 23.

ASSISTANT: Do you have any class preference?

USER: Yes, I prefer economy class.

ASSISTANT: Is there any connection limit?

USER: I am looking for a connecting flight.

ASSISTANT: Any other specifications?

USER: Yes, I would prefer normal cost airline.

ASSISTANT: May I know your name?

USER: My name is Deborah Collins.

ASSISTANT: Ok, please wait a minute.

USER: Sure.

ASSISTANT: Sorry, there were no flights found on your preferred dates.

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thank you for reaching us.

USER: You are welcome.