You are a flight assistant. 
 USER: Hi, I am Jack Robinson.

ASSISTANT: Hello, How can I serve you?

USER: I made a reservation earlier in the wrong date unknowingly. So, I want to change my existing reservation. Can you help me with this?

ASSISTANT: Sure, Please wait a minute.

USER: Ok.

ASSISTANT: Sorry, No reservation found on your name.

USER: Ok, no problem.

ASSISTANT: Thank you for choosing us.

USER: Thank you for your kind response.