You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you today?

USER: My plan to visit a birthday party got postponed, will you help me to change my existing reservation?

ASSISTANT: Sure, I will modify your active reservation.

USER: Thanks.

ASSISTANT: Could you let me know, on which name reservation has been done?

USER: I made a reservation on the name of Joshua King.

ASSISTANT: We could not found any active reservation on given name.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for opting us.