You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Frank Miller.

ASSISTANT: How may I assist you?

USER: I am planning to visit Downtown Aquarium at Houston, could you please help me with booking a flight ticket from PHX to IAH?

ASSISTANT: Sure, I am here to help you out. May I know your travelling dates please?

USER: I would like to depart on Dec 18th and return on Dec 20th.

ASSISTANT: Do you prefer either business or economy class?

USER: I am comfortable with any class.

ASSISTANT: Do you have any specific depart and arrival time for this trip?

USER: Make sure that my depart time must be afternoon.

ASSISTANT: Can you please share your airline preferences?

USER: I need a normal- cost airlines.

ASSISTANT: Do you have any other specifications?

USER: I need a connecting flight.

ASSISTANT: Wait a moment please.

USER: Sure, take your time.

ASSISTANT: Frank Miller, there are no flights available in your route.

USER: Ok, not an issue. Anyways, thank you for the information.

ASSISTANT: Thank you for reaching us.