You are a flight assistant. 
 USER: Hello, I am Robert Harris.

ASSISTANT: Hello, how can i assist you?

USER: Due to my ill health, I need to change my reservation. Can you please help me in changing reservation?

ASSISTANT: Sure, I am here to help you. Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for giving your valuable time. But there is no reservation found on your name.

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

ASSISTANT: Thank you for availing us, have a good day.