You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: I want to change an existing reservation due to sudden change in my trip.

ASSISTANT: Sure, can you please help me with your name?

USER: I am Jacob Carter.

ASSISTANT: Thank you for your details. Sorry, we did not found any reservation on your name.

USER: No issue. Thank you for your response.

ASSISTANT: Thank you for reaching us.