You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I help you today?

USER: Myself Gregory Adams from Las Vegas. I want to change my travel dates in my previous reservation. Can you please help me with that?

ASSISTANT: Sure, I will help you with that.

USER: Thank you for your response.

ASSISTANT: Please wait a while.

USER: Ok.

ASSISTANT: Thank you for waiting.

USER: It's ok.

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

USER: Oh! It's ok no problem. Thank you for your information.

ASSISTANT: Thank you for reaching us.