You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: I am Ryan Johnson.

ASSISTANT: Ryan, how may I render you?

USER: Due to the heavy rains, I would like to change my reservation. Hope you are helping me out.

ASSISTANT: Sure, I can help you. Please give me a moment to check your ticket status.

USER: Ok, take your time.

ASSISTANT: Sorry, no reservation is available by your name.

USER: It's ok, thanks for checking.

ASSISTANT: Thank you for choosing us.