You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I oblige you today?

USER: In the last month, I have reserved a flight ticket on my name to spend sometime with my family, but suddenly there is an exam on the same date. Can you please help me to modify my journey dates?

ASSISTANT: Sure, I am glad to help you.

USER: Thank you.

ASSISTANT: To check the reservation list, could you please share me your name?

USER: Sure, you can check my reservation on the name of Sandra Clark.

ASSISTANT: Ok, please wait for a couple of minutes.

USER: Sure, I will wait for your response.

ASSISTANT: Thanks for your valuable time. We are sorry to inform you that, we did not find any reservation on your specified name.

USER: Ok, no worries at all. Thanks for your service.

ASSISTANT: Thank you for approaching us.