You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I guide you for today?

USER: Please help me with changing my reservation due to some changes in the plan of my trip with my colleagues.

ASSISTANT: I am here to help you in changing your reservation.

USER: Thank you.

ASSISTANT: Can you please provide your name to check the reservation status with your name in  our booking list?

USER: Sure, my name is Eric Walker.

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

USER: No issues, thank you for your time.

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