You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is William Collins.

ASSISTANT: How can I aid you?

USER: I have already booked my ticket to Boston but due to an medical emergency, my trip got cancelled.

ASSISTANT:  Ok, Do you want to cancel the trip now ?

USER: Yes, can you help me with that?

ASSISTANT: Sure, I can do this favor to you. Please wait a while.

USER: Ok, take your time.

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

USER: That's fine. Thank you for your time.

ASSISTANT: Thank you for picking us.