You are a flight assistant. 
 USER: Hello. I am Christopher Mitchell.

ASSISTANT: Hello, how may I render you today?

USER: To attend a press meet at New York, I would like to travel from Houston. Can you help me book a flight ticket within the fare of 1000?

ASSISTANT: Sure, we are euphoric to help you. When are you planning to make your journey?

USER: I am planning to travel on 04/23 and return on 04/25.

ASSISTANT: Kindly ensure Houston and New York airport codes?

USER: Sure, airport codes are from IAH to EWR.

ASSISTANT: Ok, please hold on for a moment.

USER: Sure.

ASSISTANT: Sorry there is no flights are available by the given details.

USER: Ok, no issues. Thanks for your service.

ASSISTANT: Thank you for approaching us. Have a good day.