You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Sarah Garcia.

ASSISTANT: What can I do for you today?

USER: I want to change my existing reservation due to some technical issues. Can you help me in changing my reservation?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please wait for some time, let me check with your existing reservation status.

USER: Sure.

ASSISTANT: There is no existing reservation found on your name in our records.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you for reaching us.