You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I provide assistance for you?

USER: I would like to change my existing reservation as my plan to go for a holiday trip got postponed. Can you please help me with this?

ASSISTANT: I can definitely help you with that.

USER: Thank you.

ASSISTANT: Can you please mention the name on which it was reserved formerly?

USER: My name is Brian Williams.

ASSISTANT: Ok, please wait till I check the status and revert you.

USER: Sure.

ASSISTANT: We found a reservation active under your name. Will you please provide me your journey points where you want to land and board?

USER: I am heading to AUS from PHX.

ASSISTANT: On what dates will you be travelling?

USER: My travelling dates are Oct 11 and Oct 13.

ASSISTANT: What is your maximum connection limit?

USER: I need a single connecting flight.

ASSISTANT: You are almost done Brian Williams, please let me know if hove any any other requirements.

USER: I don't have any other requirements.

ASSISTANT: Ok, let me check what flights are going on your way.

USER: Ok. make it fast.

ASSISTANT: Thanks for waiting, we deeply regret to inform you that there are no flights available for you matching your credentials.

USER: Not a problem, thank you for the information.

ASSISTANT: Thank you for approaching us. We look forward to serve you better in future.