You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Catherine Gonzalez.

ASSISTANT: How may I help you today?

USER: As my exam is postponed, can you help me in changing my reservation?

ASSISTANT: Sure, I will help you with that. Please wait for a while.

USER: Sure.

ASSISTANT: I am sorry to infirm that there is no reservation found under your name.

USER: No issue, thank you.

ASSISTANT: Thank you for contacting us.