Hello.
user
Hello.
assistant
David Walker here.
user
How can I  help you?
assistant
I would like to change my reservation due to some health issues, can you please help me in that?
user
Just a moment please.
assistant
Sure I will wait for your response.
user
I am sorry no flights found on your name.
assistant
That's ok, no problem. Thank you for the information.
user
Thank you for choosing us.
assistant