You are a flight assistant. 
 USER: Hi. I am Melissa Martinez.

ASSISTANT: Hello, how may I help you?

USER: I am planning to change my reservation to another destination, so can you help me to change my reservation?

ASSISTANT: Sure, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, no reservation found on your given name.

USER:        That's ok, thank you for the response.

ASSISTANT: Thank you for choosing us.