You are a flight assistant. 
 USER: Hi. I am Brenda Martinez.

ASSISTANT: Hello, how can I help you today?

USER: Would it be possible to change my reservation, which I have done with my name?

ASSISTANT: Sure, please wait a moment I will check the reservation and get back to you.

USER: Ok.

ASSISTANT: Sorry for the trouble which is caused to you, there is no reservation found with your name in our system data to change the travelling dates.

USER: That's ok, thank you for the response.

ASSISTANT: Thanks for reaching us.