You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, please let me know what kind of service your looking for?

USER: I want to alter my recent reservation due to some changes in my plan. Please help me in changing my reservation.

ASSISTANT: Sure, please provide your good name.

USER: My name is Stephen Young.

ASSISTANT: Your reservation is found, May I know your planned trip dates?

USER: That's happy to hear, my trip dates are from Jan 28 to 30.

ASSISTANT: Can I know your source and destination airport codes?

USER: My source and destination airport codes are PHL and HOU.

ASSISTANT: Is there any class preferences for you?

USER: No, I am ok with any of the class.

ASSISTANT: Please share me your connection limit.

USER: I need a single connection limit.

ASSISTANT: May I know your other specifications?

USER: I am looking for normal cost airline.

ASSISTANT: Please hold on a moment.

USER: Sure.

ASSISTANT: Sorry to say that, there are no flights available based on your details.

USER: It's ok, thank you for your help.

ASSISTANT: Thank you for communicating with us.