You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

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

ASSISTANT: Sure, I am here to help you for changing.

USER: Thank you.

ASSISTANT: Ok, please provide your good name.

USER: I am Thomas Turner.

ASSISTANT: Ok, please wait.

USER: Sure.

ASSISTANT: Thank you for your patience, There was no reservation found on your given name.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for opting us.