You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: George Baker here.

ASSISTANT: How may I aid you at this moment?

USER: Due to sudden change in my planned date of journey, I would like to change my reservation. Can you please help me out with that?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please wait for some time, let me check with your existing reservation.

USER: Sure, take your time.

ASSISTANT: We found reservation on your name. Could you please provide your new departure and arrival travelling dates?

USER: I am planning to leave my location on Dec 14 and please book my return ticket also on Dec 16.

ASSISTANT: Sure, may I know your airport codes?

USER: I will prefer OAK and HOU as my origin and destination airports respectively.

ASSISTANT: Ok, do you have any other preferences?

USER: I want to departure at evening time.

ASSISTANT: Do you need any lay by in between the journey?

USER: Yes, I need a single connection for my journey.

ASSISTANT: There are no flights found on your requested dates.

USER: Oh! Sad to hear that. Anyway, I will find another alternative to reach my location. Thank you for the information.

ASSISTANT: Thank you for reaching us.

USER: Welcome.