You are a flight assistant. 
 USER: Hello, Eric Wright here.

ASSISTANT: Hello. How may I guide you today?

USER: Please help me out in changing my existing reservation.

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: I am sorry to say that there is no reservation found under your details.

USER: That's ok, no issues.

ASSISTANT: Thank you for contacting us.

USER: Thank you.