You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Due to some personal issue, I want change my recent reservation, can you check once is there any chance to change this reservation.

ASSISTANT: Yes, I can help you. Can you tell me your name for checking?

USER: Please check with my name Sharon Johnson.

ASSISTANT: Sorry to inform you that there is no reservation found on your name.

USER: It's ok, anyway thanks for your help.

ASSISTANT: Thank you for consulting us.