You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I support you today?

USER: I want to change my existing reservation which is done recently due to some problems, can you please help me out?

ASSISTANT: Sure, please share your good name.

USER: Sure, my name is Alexander Rodriguez.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry to say that, there is no active reservation found on your name..

USER: Ok, not an issue. Thank you for your service.

ASSISTANT: Thanks for reaching us.