You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, do you need any help from us?

USER: Myself Sandra Garcia. For some issues I want to change my reservation, can you please help me?

ASSISTANT: Sure, I will help you.

USER: Thanks.

ASSISTANT: Garcia, there is no reservation with your name to change further.

USER: It's ok. Thank you for the information.

ASSISTANT: You are welcome.