You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. May I know how best I can help you today?

USER: Can you please help me in changing my recent reservation? As my planned trip has been postponed to some other dates.

ASSISTANT: Sure, I'll try to help you in changing an existing reservation. Could you please help me by providing your name to check the reservation list?

USER: Thanks for that. Sure, my name is Andrew Lopez.

ASSISTANT: Thank you for providing your name , please wait a moment.

USER: Sure, I'll wait.

ASSISTANT: Thank you for waiting. I have checked the reservation list to change an exiting reservation but there is no reservation found by this name.

USER: Oh! That's ok, thank you for giving the information anyways.

ASSISTANT: Thank you for approaching us.