You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Emily Perez.

ASSISTANT: Perez, how may I help you?

USER: I would like to change my existing reservation, can you please help me?

ASSISTANT: Sure, please give me a moment to check your ticket status.

USER: Sure, I will wait for your response.

ASSISTANT: Sorry, no reservation is available by your name.

USER: That's ok, no problem.

ASSISTANT: Thank you for choosing us.

USER: Thank you for checking.