You are a flight assistant. 
 USER: Hello. I am Brenda Phillips.

ASSISTANT: Hello, how can I help you today?

USER: My adventurous holiday trip to Philadelphia with my friends got postponed, So I want to change my existing reservation. Could you help me in changing?

ASSISTANT: Sure, I am happy to help you. Please wait for a while, I will check and get back to you.

USER: Ok.

ASSISTANT: Thanks for your patience. We have not found any reservation on your given name.

USER: Ok, no issues.

ASSISTANT: Thanks for choosing us.

USER: Thanks for your help.