You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER:  I am Ryan Roberts want to change my reservation due to prepone of my meeting. Can you help me in changing?

ASSISTANT: Sure, give me a minute.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: Ok, no issues.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your help.