You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you?

USER: I want to change my existing reservation due to bad health conditions. Can you help me?

ASSISTANT: Sure, please share your good name?

USER: I am Dennis Thomas.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your given name.

USER: Ok, no issues.

ASSISTANT: Thank you for choosing us.

USER: Thanks for the information.