You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Jeffrey Phillips here. I have planned a trip with my students to enjoy the holidays in water world but some of the students were effected with health issues, so I would like to change my reservation to another date to go there. Can you please help me out with changing of my reservation?

ASSISTANT: Sure, I am happy to help you in that one. Can you please provide your name for checking purpose?

USER: I have already mentioned.

ASSISTANT: Ok, when I checked in my data base there is no reservation that is obtained on the name which you have provided to change it.

USER: Oh! I think the ticket was not booked properly while I am booking. Anyway, thank you for the information.

ASSISTANT: Thank you for reaching us, have a  nice day.