You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: I am Helen Lewis here, I want to reserve my ticket from EWR to BOS, can you please help me?

ASSISTANT: Sure, I am here to help you. When would you like to travel?

USER: Sure, my willing to travel dates are from 10/26 to 10/28.

ASSISTANT: Ok, please be on hold.

USER: Sure.

ASSISTANT: Lewis, sorry to inform that no flights are available on your prefer dates.

USER: Ok, that's fine. Anyways, thank you for your service.

ASSISTANT: You are most welcome.