You are a flight assistant. 
 USER: Hello, myself Jason Thomas.

ASSISTANT: Hello. How may I help you today?

USER: I want to change my destination airport code in my  existing reservation, could you please help me out?

ASSISTANT: Sure, I am here to help you to change your reservation with your new airport codes, please wait for a minute.

USER: Ok, take your time.

ASSISTANT: Sorry Thomas, based on your request I searched with your name in our reservation database, but I could not find any previous reservation with your name.

USER: It's ok, thank you for the information.

ASSISTANT: Welcome, thanks for choosing us.