You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I serve you?

USER: Ashley Martinez on this end.

ASSISTANT: Nice to meet you Ashley.

USER: Due to sudden change in my planned date of journey, I would like to change my reservation. Can you please help me out with changing of my reservation to new dates?

ASSISTANT: Yes, please I will help you with the change of flight ticket reservation.

USER: Thank you.

ASSISTANT: Thanks for waiting patiently. But I regret to inform you that there is no flight reservation on your name to change it.

USER: How can you say like that, I have a confirmation message from your agency. Please recheck once again.

ASSISTANT: Sorry for the inconvenience caused. I have reconfirmed your flight reservation status but still it is showing the same result.

USER: It's ok, I will contact with your higher authorities. Anyway, thank you for the information.

ASSISTANT: Thank you.

USER: Welcome.