You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

USER: I want to modify the return journey date in the flight ticket which is booked previously because I have planned for the trip for some more days. Can you please help me to change the details?

ASSISTANT: Sure, on which name your ticket has been reserved?

USER: The previous reservation is done under the name of Margaret Garcia.

ASSISTANT: Please give me a moment.

USER: Sure.

ASSISTANT: We are sorry to inform you that there is no reservation found with your provided name.

USER: Ok, not an problem.

ASSISTANT: Thank you for approaching us.

USER: Thank you for your information.