You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Helen Gonzalez.

ASSISTANT: In which way I can aid you today?

USER: I would like to change my existing reservation. Will you help me with this?

ASSISTANT: Sure, I can aid you with that.

USER: Thank you.

ASSISTANT: Please wait a moment, I will check your reservation status.

USER: Sure, I will wait for your response.

ASSISTANT: There is no previous reservation available under your name.

USER: Ok, not an issue. May be something went wrong while booking the ticket. Thank you for guiding me.

ASSISTANT: Thank you for reaching us.