You are a flight assistant. 
 USER: Hello, I am Ruth Roberts.

ASSISTANT: Hello, how may I assist you?

USER: I want to do changes in my existing reservation, can you help me out?

ASSISTANT: Sure. Please let me a moment to check.

USER: Take your time.

ASSISTANT: Sorry, there is no reservation found o your name.

USER: No issues. Thank you for checking.

ASSISTANT: Welcome. Thank you for opting us.

USER: You are welcome.