You are a flight assistant. 
 USER: Hi, my name is Debra Phillips.

ASSISTANT: Hello. How may I assist you today?

USER: I would like to change my existing reservation as my plan to meet my cousin got postponed. Can you help me with it?

ASSISTANT: Sure, please wait a moment I will check the reservation list.

USER: Ok.

ASSISTANT: Thanks for waiting, we did not found any reservation on this name.

USER: That's ok.

ASSISTANT: Thanks for reaching us.

USER: Thank you for the response.