You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: Could you please help me to change an existing reservation as my plan to meet my grand parents got postpone due to my health issues?

ASSISTANT: Sure, may I know your good name?

USER: I am Donna Phillips.

ASSISTANT: Please wait.

USER: Sure.

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

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

ASSISTANT: Thank you for choosing us.