You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I render you today?

USER: Can you help me to change my recent reservation?

ASSISTANT: Sure, I am here to help you. May I know on whose name the ticket has been reserved formerly?

USER: Jacob Hernandez here.

ASSISTANT: Sorry Jacob Hernandez, there are no flights reserved on your given name formerly.

USER: Ok, thank you for checking.

ASSISTANT: Welcome, thank you for choosing us. Have a great day.