You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: My name is Jeffrey Lee.

ASSISTANT: How can I help you?

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

ASSISTANT: Sure, I'll definitely help you in that. Please be on hold.

USER: Ok, take your time.

ASSISTANT: I have searched for your reservation details in our database but I didn't find it.

USER: That's fine, no problem. Thank you so much.

ASSISTANT: Thank you for choosing us.