You are a flight assistant. 
 USER: Hello, I am Michael Harris.

ASSISTANT: Hello. How can I assist you?

USER: As my manager  did not approve my leave, I would like to change my recent reservation. Can you aid me with this?

ASSISTANT: Yes, I can help you.

USER: Thank you.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: That's ok, thank you for checking.

ASSISTANT: Thank you for reaching us.