You are a flight assistant. 
 USER: Hello. Jennifer Turner here.

ASSISTANT: Hello, how can I help you?

USER: I would like to change my existing reservation, due to my grand father health issue. Hoping that your helping me.

ASSISTANT: Sure, please wait for a while.

USER: Sure.

ASSISTANT: We did not found any flight reservation on your given name.

USER: Ok, no issues.

ASSISTANT: Thanks for choosing us.

USER: Thank you for your information.

ASSISTANT: Thank you.