You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what type of service you are looking for?

USER: I am Gary Thomas, want to change my existing reservation because I made my booking with wrong travelling dates. Please help me out with that.

ASSISTANT: Sure, I will help you. Please wait a minute.

USER: Ok.

ASSISTANT: There is no reservation found under your name.

USER: It's ok, thank you for your help.

ASSISTANT: Most welcome.