You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Samantha Hernandez.

ASSISTANT: Samantha Hernandez, how may I aid you?

USER: Due to some client meeting, I am going to change my existing reservation. Can you please help me for this?

ASSISTANT: Sure, please give me a moment to check your ticket status.

USER: Sure, I will wait for your kind response.

ASSISTANT: Sorry, no reservation is available by your name.

USER: Not a big problem, anyway thank you very much for your service.

ASSISTANT: Thank you for contacting us.