You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Joshua Garcia.

ASSISTANT: How can I help you?

USER: Due to some issues, I want to alter my reservation dates. Can you please help me in this?

ASSISTANT: Sure. please wait for a while. Let me check your reservation ststus in our database.

USER: Sure, take your time.

ASSISTANT: Sorry, we couldn't found any reservation in our database.

USER: It's ok, thank you.