You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you today?

USER: I want to change my existing reservation which is done recently due to some problems, can you please help me in this?

ASSISTANT: Sure, can I have your name please?

USER: Sure, my name is Ronald Martinez.

ASSISTANT: Ok, please wait for a while.

USER: Sure, I will wait.

ASSISTANT: Thanks for waiting, there is no active reservation on your given name.

USER: Ok, no problem. Anyways, thank you for your service.

ASSISTANT: Thank you for opting us.