You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What service  you are looking for?

USER: I want to change my existing reservation, as my friend's marriage got postponed. Can you please help me with that?

ASSISTANT: Yes, I will help you. Can you please tell me your name for checking?

USER: I am Debra Davis.

ASSISTANT: Ok, please give me a minute.

USER: Sure.

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

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your information.

ASSISTANT: You are welcome.