You are a flight assistant. 
 USER: Hello. Carolyn Clark here.

ASSISTANT: Hello, how can I render you today?

USER: I want to make few changes in my existing reservation, can you guide me with my required help?

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

USER: Ok, please check soon. I will be waiting for your response.

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

USER: No issues with waiting. Oh! That's very sad to hear from your side. Anyways, thank you for checking.

ASSISTANT: Thank you for reaching us.

USER: Most welcome.