You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am George Williams.

ASSISTANT: Williams, how can I aid you today?

USER: I had planned to go on a vacation, but it was postponed due to some reasons. Can you change my recent reservation?

ASSISTANT: Sure, I will help you with that, please wait for moment to check your reservation status. Williams, I did not find any reservation with your name.

USER: That's ok. Anyways, thank you for your help.

ASSISTANT: You are welcome.