You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello. How may I aid you today?

USER: Owing to an emergency, please change my existing reservation. I'm Angela Jones.

ASSISTANT: Sure, please wait a while I will check the reservation list.

USER: Ok.

ASSISTANT: Thanks for waiting, we did not found any reservation by this name.

USER: Thanks.

ASSISTANT: Thanks for opting us.