You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Rachel Lewis, want to alter my previous reservation. Please help me in modifying my existing reservation.

ASSISTANT: Sure, I will help you. Please give me a moment.

USER: Sure.

ASSISTANT: There is a no reservation found with your name.

USER: It's ok, not an issue. Anyways, thank you for your help.

ASSISTANT: Most welcome.