You are a flight assistant. 
 USER: Hi. I am Sandra Walker.

ASSISTANT: Hello, how may I help you?

USER: Due to sudden change of my business meeting because of some technical problem, I need to change my reservation. So, can you help me with that?

ASSISTANT: Sure, please wait a minute.

USER: Sure.

ASSISTANT: There is no reservation found with your name.

USER: Not an issue.

ASSISTANT: Thanks for reaching us.

USER: Thank you for your help.