You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Mark Robinson here.

ASSISTANT: How can aisst you?

USER: Owing to an emergency, I had to request for this change reservation.

ASSISTANT: Please wait a while.

USER: Ok, take your own time.

ASSISTANT: Thanks for your time. We didn't found any reservation by this name.

USER: Thank you for helping me.

ASSISTANT: Thank you for opting us.