You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you at this moment?

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

ASSISTANT: I feel happy to help you in changing your reservation. Could you please let me know your name to search the reservation status with your name?

USER: Gregory Lewis here.

ASSISTANT: Sorry for the trouble which is caused to you, I have not found any reservation on your name in our database.

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

ASSISTANT: You are welcome, thank you for reaching us.