You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I am Betty Collins, can you help me for changing existing reservation?

ASSISTANT: Ok, please wait.

USER: Ok, I will wait for your response.

ASSISTANT: Sorry, there was no reservation find on your name.

USER: Oh! It's ok, no problem. Thank you for your services.

ASSISTANT: Thank you for selecting us.