You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello.

USER: I am Kenneth Garcia.

ASSISTANT: How can I aid you at this moment?

USER: I want to change my existing reservation. Please help me out.

ASSISTANT: Sure, please wait for a while.

USER: Ok'.

ASSISTANT: Sorry Kenneth Garcia, no reservation found on your name.

USER: No issues, thank you.

ASSISTANT: Thank you for approaching us.