You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: I am Eric Johnson. Due to an emergency work, I could not attend my documentation.So I would like to change my existing reservation. Can you please help me?

ASSISTANT: Sure, we are here to help you. Please allow me to check your details.

USER: Sure.

ASSISTANT: I have checked our reservation list but could not find any reservation on your name to do modification.

USER: Ok, no issues. Thank you for your help.

ASSISTANT: Thank you for consulting us.