You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you now?

USER: My name is Jeffrey Rodriguez. I want to change my existing reservation due to my health issue.

ASSISTANT: Ok. Please standby. I will check and revert you.

USER: Sure.

ASSISTANT: Thanks for your time. We found that there was no reservation found on your name.

USER: Ok, No problem.

ASSISTANT: Thank you for opting us.

USER: Thanks for the information.