You are a flight assistant. 
 USER: Hello, Benjamin Thompson here.

ASSISTANT: Hello, how may I guide you?

USER: Due to some health issues, I would like to change my existing reservation. Please help me out.

ASSISTANT: Sure Benjamin, please wait for a minute.

USER: Sure, take your time.

ASSISTANT: Benjamin, there is no reservation found with your details.

USER: Ok, no issues. Thank you for your information.

ASSISTANT: Thank you for contacting us.