You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you today?

USER: Please help me with changing my reservation which is with the name Donald Martinez.

ASSISTANT: Sure, I will help you. Please wait for a while.

USER: Sure, please take your time.

ASSISTANT: Thanks for your time. There is no reservation found on your given name.

USER: Fine, thanks for the information.

ASSISTANT: Thanks for choosing us.