You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you out?

USER: I am Dennis Garcia, can you help me to modify my reservation as my schedule got postponed to some other day?

ASSISTANT: Sure, I am here to help you. Please wait a minute.

USER: Thank you for considering my request. Sure, I will wait for your response.

ASSISTANT: Thanks for waiting, we found a reservation on your name. Can you please let me know your travelling dates to proceed further?

USER: Good to hear, my travelling dates are Apr 12 and Apr 14.

ASSISTANT: Please help me with your respective airport codes.

USER: Sure, my respective airport codes are OAK and ORD.

ASSISTANT: Ok, do you prefer any lay by in between journey?

USER: Yes, I need a lay by in between my journey.

ASSISTANT: Ok, are you looking for economy class itself or any other class?

USER: I am comfortable with any of the class.

ASSISTANT: Thanks for providing details, no flights are available on your journey routes.

USER: Not an issue, anyways thank you for the information.

ASSISTANT: Thank you for reaching us.

USER: You are welcome.