You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Sarah Smith this side.

ASSISTANT: How can I guide you?

USER: As my manager did not approve my leave, so I want to change my reservation. Can you please help me?

ASSISTANT: Sure Smith, I am here to help you.

USER: Thank you.

ASSISTANT: Just give a moment to check your previous reservation which you have booked.

USER: Ok.

ASSISTANT: Sorry Smith, I can't help you in changing in your reservation because in our data base there is no reservation is showing.

USER: No problem, It's ok. Thank you for checking.

ASSISTANT: You are welcome. Thank you for connecting us.