You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I have to change my reservation due to my planned event got postponed. So please  help me with that.

ASSISTANT: May I know your name please?

USER: Thank you. Please check the reservation with my name Donna Hernandez.

ASSISTANT: Sorry, there is no reservation found in our database.

USER: Oh! It may not be booked properly due to server issues while booking. Anyway, thank you for your time.

ASSISTANT: Thank you for choosing us.

USER: Most welcome.