You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you?

USER: I am Ruth Green. Due to my health problem, I want to change my resent reservation, can you please help me in that?

ASSISTANT: Sure, let me check the current status and revert you.

USER: Ok.

ASSISTANT: We could not find any reservation by the name you provided.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for reaching us.