You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I render you today?

USER: Richard Garcia here.

ASSISTANT: Ok.

USER: I need to change my recent reservation because my trip dates are postponed.

ASSISTANT: Sure, I will help you with that. Please wait a moment.

USER: Ok, take your own time.

ASSISTANT: Thank you for waiting. I have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.