You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I render you?

USER: My name is Ashley Clark. I want to celebrate my birthday at Golden gate Bridge at San Francisco, SFO. Can you help me in booking a flight ticket under the range of 1000?

ASSISTANT: Sure, may I know your travelling dates?

USER: My travelling dates are from 05/16 to 05/18.

ASSISTANT: What is your source airport code?

USER: My source is Houston, HOU.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thanks for being waiting.

USER: Ok.

ASSISTANT: Unfortunately, there is no flight available on you travelling dates.

USER: Ok, No problem. Thanks for the information.

ASSISTANT: Thanks for communicating us, have a great day.