You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Alexander Clark.

ASSISTANT: How may I assist you at this moment?

USER: Could you be my helping hand in changing my existing reservation?

ASSISTANT: Please wait for a minute.

USER: Ok.

ASSISTANT: We are great to inform you that, there is no reservation found on your name in our database.

USER: No issues, thank you for your information.

ASSISTANT: Thank you for reaching us.