You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I have given some wrong details while booking earlier so I would like to change my reservation so please help me with that.

ASSISTANT: Sure, I can assist you with that.

USER: Thank you.

ASSISTANT: May I know your name for checking your previous reservation status?

USER: Sure, please check the reservation with my name Gary Walker.

ASSISTANT: Ok, please wait a moment.

USER: Sure, take your time.

ASSISTANT: There is no previous reservation found on your name Gary Walker.

USER: Oh! May be booking has not done properly due to technical issue. Anyway, thank you for your valuable time.

ASSISTANT: You are welcome.