You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I support you?

USER: I am Jonathan Nelson. Due to sudden changes in climate, I was fallen sick.So I would like to change my existing reservation. Can you please help me in changing?

ASSISTANT: Sure, I can help you with it. Please wait for a while. I will check the reservation list.

USER: Sure.

ASSISTANT: Thanks for waiting. Sorry to inform you that there was no reservation found on your name.

USER: Ok, no worries at all. Thank you for your great information.

ASSISTANT: Thank you for connecting with us.