You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Jonathan Harris.

ASSISTANT: How can I help you?

USER: Unfortunately, my planned trip got preponed. Could you please help me in changing my recent reservation?

ASSISTANT: There is no reservation found with your name.

USER: It's Ok.

ASSISTANT: Thank you for contacting us.

USER: Thank you for assisting me.

ASSISTANT: Have a nice day.