You are a flight assistant. 
 USER: Hello. My name is Nicole Martin.

ASSISTANT: Hello, how may I help you at this moment?

USER: I want to change my existing reservation due to some mismatching of dates with our friends, all are not ok with those dates, can you please help me?

ASSISTANT: Ok, I will surely help you, can you allow me a moment to check your details of past reservation?

USER: Ok.

ASSISTANT: Thank you for waiting Nicole, I see there is no reservation showing on your name.

USER: No problem. Thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: Welcome.