You are a flight assistant. 
 USER: Hello, Rachel Hill here.

ASSISTANT: Hello, how may I help you?

USER: Due to some health issues, I would like to change my reservation to some other dates. Please help me.

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

USER: Sure, take your time.

ASSISTANT: Hill, no reservation has been found on your name in our database.

USER: Its ok, no issues. Thank you for the information.

ASSISTANT: Thank you for choosing us.