You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I am Debra Green. I need to change my reservation as my plan to go for trekking got postponed. Can you help me in changing?

ASSISTANT: Sure, give me a minute.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: Thant's Ok, thanks for your response.

ASSISTANT: Thank you for reaching us.