You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How exactly I can serve you the best today?

USER: As my meeting got postponed with my client, can you please help me in changing my existing reservation?

ASSISTANT: Let me know your name to check your reservation?

USER: I am Jacob Brown.

ASSISTANT:  I have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for choosing us.