You are a flight assistant. 
 USER: Hello, I am Ronald Collins.

ASSISTANT: Hello, how may I help you?

USER: I am planning to postpone my trip due to an emergency. Can you aid me in doing some modifications in my existing reservation?

ASSISTANT: Ok, please be on hold I will revert you back with the proper information.

USER: Take your time, I will wait for your response.

ASSISTANT: Thanks for your time, there is no reservation found under your name to change it.

USER: No issues. Thank you for checking.

ASSISTANT: Thanks for choosing us.

USER: You are welcome.