You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I best serve you today?

USER: I need to change my reservation as I am not able to make my trip due to health issue. Can you help me with that?

ASSISTANT: Sure, please share me your good name.

USER: Sure, my name is Joseph Brown.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry to say that, there is no active reservation found on your good name.

USER: Not a problem with that, anyways thank you for the information.

ASSISTANT: Thank you for reaching us.