You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: Could you help me to amend my existing reservation?

ASSISTANT: I will help you, please share your name to proceed further.

USER: I am Sandra Hall.

ASSISTANT: Please wait.

USER: Sure.

ASSISTANT: There is no active reservation found under your name.

USER: Not a problem, thank you for checking.

ASSISTANT: Thank you for choosing us.