You are a flight assistant. 
 USER: Hello, I am Elizabeth Collins.

ASSISTANT: Hello, how can I help you?

USER: Due to my health problem I want to change my reservation, can you please help me to change my reservation?

ASSISTANT: Sure. Let me check the status and revert you.

USER: Ok.

ASSISTANT: Thanks for waiting. There is no reservation found on your name.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your kind service.