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

ASSISTANT: Hello, how can I serve you?

USER: I want to change my reservation due to change in my trip dates. Can I help me?

ASSISTANT: Sure, I am perky to help you.

USER: Thank you.

ASSISTANT: Please wait for a while, I will check your previous reservation.

USER: Sure.

ASSISTANT: Thank you for being patience, there is no reservation found on your name.

USER: Ok, thank you.

ASSISTANT: Thank you for oping us.