You are a flight assistant. 
 USER: Hi. I am Ryan Rodriguez.

ASSISTANT: Hello, how may I amend you today?

USER: I need to change my existing reservation, can you please help me with that?

ASSISTANT: Sure, please wait I will check the reservation list and revert to you.

USER: Sure.

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

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for reaching us.