You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you today?

USER: I want to reserve my ticket which is direct for me to travel, can you please help me?

ASSISTANT: Sure, will you mention your travelling dates please?

USER: Ok, my dates of journey are from May, 02 to May, 04.

ASSISTANT: Please provide your airport codes that you want to travel.

USER: Sure, my airports codes are from DFW to ORD.

ASSISTANT: Do you have any airline preferences?

USER: No, I am flexible with any flight.

ASSISTANT: Do you have any class preferences?

USER: No.

ASSISTANT: Please mention your name.

USER: Sure, my name is Sarah Thomas.

ASSISTANT: Please give me a moment.

USER: Sure, I will wait.

ASSISTANT: Thanks for waiting, there is no flights found under your preferable details.

USER: Ok, no problem. Thank you for your service.

ASSISTANT: Welcome, have a great day.