You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Alexander King here.

ASSISTANT: How may I help you?

USER: As my planned trip has been postponed to some other dates, I need your help in changing my recent reservation. Can you help me in that?

ASSISTANT: Sure, I will help you. Please, wait a minute.

USER: Sure, I'll wait for your response.

ASSISTANT: Thank you for waiting, there is no reservation found on your name to proceed for modification.

USER: Oh! May be I have done a wrong booking, thank you anyways.

ASSISTANT: Thank you for reaching us.