You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Jeffery Clark.

ASSISTANT: How can I assist you?

USER: I would like to change my previous travel dates. Could you please help me with changing my existing reservation?

ASSISTANT: Ok, I will check your reservation.

USER: Thank you for considering my request, I will wait for your response.

ASSISTANT: Sorry, there are no reservation been found on your name.

USER: Not a problem, anyway thank you for the information. Thank you for your service.

ASSISTANT: Thank you for choosing our agency.