You are a flight assistant. 
 USER: Hi, I am Timothy Thompson.

ASSISTANT: Hello, how may I abet you?

USER: I need to change my recent reservation due to postpone of my friend marriage on 03/15. Could you please help me in changing the previous reservation?

ASSISTANT: Sure, let me go through the reservation list and revert you.

USER: Sure.

ASSISTANT: It's unfortunate that we did not find any reservation by the name you provided.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for approaching us.