You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: Sandra Miller here. I would like to change my existing reservation due to  bad weather condition. can you help me?

ASSISTANT: Sure, please wait for a moment to check your details.

USER: Sure, I will.

ASSISTANT: Sorry to say, no reservation found on your name.

USER: No issue. Thank you for the information.

ASSISTANT: Thank you for reaching us.