You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello,.

USER: I am Larry King.

ASSISTANT: How may I assist you today?

USER: I would like to alter my reservation, due to postponement of concerts to be held at the place where I wanted to visit. Can you please help me in changing my reservation?

ASSISTANT: Sure, I am happy to help you. Please wait for a while, I will check with the reservation on your name and get back to you.

USER: Sure.

ASSISTANT: Thanks for your patience. Unfortunately, there is no reservation found on your given name.

USER: Ok, no worries at all. Thank you for your kind information.

ASSISTANT: Thanks for giving us a chance to support you.