You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I serve you?

USER: As, My manager didn't approved my leave, so I want to change my reservation. Can you help me with that?

ASSISTANT: Sure, I will help you. Please provide the name on which ticket was reserved.

USER: Thank you for taking my request into consideration.

ASSISTANT: Welcome.

USER: The ticket has been reserved under the name of Emily Harris.

ASSISTANT: Sorry, there is no reservation existing on your name.

USER: Ok, thank you.

ASSISTANT: You are welcome, have a nice day.