You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: Virginia Hernandez 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: Yes, I can help you. Sorry to inform you that there is no reservation found on your name.

USER: Oh! I think the ticket was not booked due to server issue. Anyway, thank you for the information.

ASSISTANT: Thank you for reaching us.

USER: Welcome.