You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I would like to change my reservation due to some health issues, can you please help me out with that?

ASSISTANT: Your name please.

USER: Myself Justin Garcia.

ASSISTANT: Sorry Justin Garcia, there is no reservation found under your name.

USER: Ok, no problem. Thank you for checking.

ASSISTANT: Thank you for using our service.