You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, Good Afternoon.

USER: Very good after noon, I'm Thomas Moore.

ASSISTANT: Ok Thomas, how may I help you?

USER: I have booked a ticket on last week but due to some issues I want to change the journey dates, can you please help me in that?

ASSISTANT: Sure, I am here to help you. Can you please give me  a minute to check the ticket status?

USER: Sure, take your time.

ASSISTANT: Thank you for waiting.

USER: It's ok.

ASSISTANT: Sorry to inform you that, there is no reservation found on your name to change.

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

ASSISTANT: Thank you for reaching us.