You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I want to change my reservation as my plan to go for trekking got postponed. Can you help me?

ASSISTANT: Sure, we are here to help you. May I know your name please?

USER: I am Samuel Scott.

ASSISTANT: Sorry to inform you that there is no active reservation on your given name.

USER: That's alright, thanks for your assistance.

ASSISTANT: Thanks for contacting us.