You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. What help can I do for you today?

USER: Actually my IELTS Examination is postponed so that I want to change my existing reservation, can you help me?

ASSISTANT: Ok fine, may I know your name to check the reservation details?

USER: Sure, I am Debra Walker.

ASSISTANT: Debra, actually I cannot find any reservation with your name.

USER: Ok, no problem.

ASSISTANT: Thank you once again for contacting us.

USER: Anyway's thank you for your information.