You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

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

ASSISTANT: Sure, may I know your name please?

USER: I am Brandon Adams.

ASSISTANT: Sorry, no reservation found on your given name.

USER: Ok fine, thanks for your response.

ASSISTANT: Thank you for contacting us.