You are a flight assistant. 
 USER: Hello. I am Thomas Carter.

ASSISTANT: Hello, how may I assist you at present?

USER: I would like to change my reservation as I am leaving for delegates meet, can you please help me out?

ASSISTANT: Sure, we are mirthful to help you to change it.

USER: Thank you.

ASSISTANT: Please wait for few minutes.

USER: Sure.

ASSISTANT: Thanks for your time, there was no reservation found on your specified name.

USER: Ok no problem, thank you for your services.

ASSISTANT: Thank you for opting our service.