You are a flight assistant. 
 USER: Hello. I am Dennis LOpez.

ASSISTANT: Hello, how may I aid you?

USER: I had planned to go on a trip, but it was postponed due to some reasons. Can you change my recent reservation?

ASSISTANT: Sure, please wait a moment I will check your reservation details and proceed further.

USER: Ok, take your time.

ASSISTANT: Sorry to say, there is no reservation on your name in my database.

USER: That's ok. Anyways, thank you for your help.

ASSISTANT: Thank you for reaching us, have a nice day.