You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: I am Patricia Phillips. I want to change my existing reservation, due to some health issue. Can you please help me out?

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Thank you for waiting.

USER: My pleasure.

ASSISTANT: There are no active reservations to change the travelling dates.

USER: That's ok, thank you for checking.

ASSISTANT: It"s my pleasure.