You are a flight assistant. 
 USER: Hi, I am Frank Walker.

ASSISTANT: Hello, how may I help you today?

USER: I want to change my reservation, can you help me with that?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please wait for some time.

USER: Sure.

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

USER: Ok, no issues. Thank you for sharing the information.

ASSISTANT: Thank you for reaching us.