You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: Kathleen Harris here. Could you book my ticket from PHX to IAH?

ASSISTANT: Sure, can you please share your travelling dates?

USER: My trip dates are Dec 26 and Dec 28.

ASSISTANT: Do you have any connection limit?

USER: I need a connecting flight.

ASSISTANT: Let me know your class preference?

USER: I prefer economy class.

ASSISTANT: Do you have any specifications?

USER: I want to return in the afternoon and I prefer normal-cost airlines.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: No problem, I will find an alternative way to travel.

ASSISTANT: Thank you for reaching us.