You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Brenda Adams here.

ASSISTANT: How can I assist you?

USER: Due to health issue, I want to postpone my trip to some other dates. Can you please help me in changing my recent reservation?

ASSISTANT: Sure, I will help you to change your reservation. Can you give me a moment to check your previous reservation.

USER: Sure, take your time.

ASSISTANT: Sorry, there is no reservation found on your name to change.

USER: That's ok, may be I have done a wrong booking. Thank you anyways.

ASSISTANT: Welcome. Thank you for choosing us.