You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: Could you please help me to change an existing reservation as my plan to meet my grand parents got postpone due to my health issues?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: I made a reservation by this name Ronald Garcia.

ASSISTANT: Ok, please stand by.

USER: Sure.

ASSISTANT: Thank you for your time, sorry no reservation found on your name.

USER: Ok, not an issue.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: Thank you for your information.