You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I would like to shift my planned dates to some other dates, please help me in changing my existing reservation.

ASSISTANT: Sure, please provide me your name to check the status.

USER: My name is Donna Miller.

ASSISTANT: Donna, please wait for a minute.

USER: Sure, take your time.

ASSISTANT: There is no reservation found with your details.

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

ASSISTANT: Thank you for contacting us.