You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I render you at this moment?

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

ASSISTANT: Sure, may I know your good name please?

USER: I am Ashley Thomas.

ASSISTANT: There is no existing reservation found on your name in our records.

USER: Ok fine, thanks for your assistance.

ASSISTANT: Thank you for reaching us.