You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you today?

USER: Myself Karen Johnson.

ASSISTANT: Ok.

USER: Houston Hop-on Hop-off trolley tour has been postponed, due to some bad weather conditions. For this, help me to change my reservation.

ASSISTANT: Sure, please give me a moment.

USER: Ok.

ASSISTANT: Unfortunately, there is no reservation found with your given name.

USER: Not a issue.

ASSISTANT: Thank you for choosing us.

USER: Thank you.