You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you?

USER: Nicholas Thompson here.

ASSISTANT: Nice to meet you Thompson.

USER: Can you help me in changing my reservation due to some health issues?

ASSISTANT: Sure,I will help you with that.

USER: Thank you for accepting my request.

ASSISTANT: Nicholas Thompson, we couldn't find any recent reservations under your name in our database.

USER: That's ok, no problem. Anyway thank you for checking out.

ASSISTANT: Thank you for reaching us.