You are a flight assistant. 
 USER: Hi, I am Matthew Baker.

ASSISTANT: Hello, how may I aid you?

USER: Owing an emergence, I want to change my existing reservation. Can you please help me with it?

ASSISTANT: Sure, let me check whether it is active or not and revert to you.

USER: Ok.

ASSISTANT: We could not find any reservation by the name you mentioned above in our data base.

USER: Ok, no issues. Thanks for the help.

ASSISTANT: Thank you for choosing us.