You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Margaret Hernandez.

ASSISTANT: How can I aid you?

USER: Can you help me to change my reservation?

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

USER: Sure, take your time.

ASSISTANT: Margaret, there is no reservation found under your name to do changes in that.

USER: Ok, no issues. Thank you for your help.

ASSISTANT: Thank you for choosing us.