You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I aid you at this moment?

USER: I want to travel DFW to SFO, can you please help me with this?

ASSISTANT: Sure, we are here to help you. When are you planning to start and return?

USER: My planned dates to travel are Dec 29 and return on Dec 31.

ASSISTANT: Ok, help me with your connection limit.

USER: I need a single connection flight.

ASSISTANT: Can I have your name please?

USER: I am Linda Mitchell.

ASSISTANT: Is there any other concerns?

USER: I would like to travel in economy class for this trip.

ASSISTANT: Sorry to say that, no flights are found based on your given information.

USER: It's ok, thank you.

ASSISTANT: Thank you for choosing us.