You are a flight assistant. 
 USER: Hi, I am Helen Williams.

ASSISTANT: Hello, how can I aid you?

USER: Due to heavy raining my cricket tournament has postponed to future dates, so could you help me in changing my existing reservation?

ASSISTANT: Sure, give me a moment.

USER: Ok.

ASSISTANT: Thanks for waiting. Sorry, no reservation is found on your name.

USER: Ok, no issues, thanks for your assistance.

ASSISTANT:  Thanks for contacting us, have a nice day.