You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am Eric Hernandez. I want to change an existing reservation, due to my health issues.

ASSISTANT: Sure, please wait for a few minutes, I will check the reservation list and revert to you.

USER: Sure.

ASSISTANT: Thank you for waiting, we are sorry to say that there was no reservation found on your name.

USER: Not an issue. Thank you.

ASSISTANT: Thank you for contacting us.