You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: My name is John Brown. Can you help me to change the reservation I had done recently?

ASSISTANT: Sure, please allow me a moment to check for your status.

USER: Ok, please take your time I will wait.

ASSISTANT: Thank you for waiting. Sorry, there is no active reservation have been found under your name in our database to amend it.

USER: Ok, thank you for assisting me with that. May be my brother had change for me.

ASSISTANT: Thank you for reaching us.