You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I abet you?

USER: Please change my reservation, which is reserved earlier in the name of Sandra Davis. Due to the busy schedule on my previously planned dates.

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait for a while, to check the present status of your earlier reservation and let you know.

USER: Sure, take your time.

ASSISTANT: Thank you for waiting.

USER: My pleasure.

ASSISTANT: I have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for the information.

ASSISTANT:  Have a blissful day!.