You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

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

ASSISTANT: Sure.

USER: I am Samuel Young.

ASSISTANT: Tell me your name please?

USER: Please check for the reservation with the above mentioned name.

ASSISTANT: Nice to meet your Samuel. Sure.

USER: Thank you.

ASSISTANT: Thanks for waiting. But I am sorry to say that there is no flight reservation on your name to change it.

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

ASSISTANT: Thank you.