You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I'm Donald Mitchell.

ASSISTANT: How may I guide you today?

USER: I would like to change my reservation which is under my name. Can you please help me with that?

ASSISTANT: Sure, I will help you with that. Please wait for a while, I will check it.

USER: Sure, take your time.

ASSISTANT: I am sorry to say that there is no reservation found under your details.

USER: Ok, no issues. Thank you for checking.

ASSISTANT: Thank you for contacting us.

USER: You are welcome.