To appeal the council's decision on your application you must follow the review procedure 

You must ask for a review within 21 days of getting the council's decision or offer letter.

If you are unhappy with the decision you need to be clear as to why the decision is incorrect (Allocations policy). If your circumstances have changed since the decision then you do not need to submit a request for a review. You will need to submit a new application if your application has been removed or a change of circumstances if you still have an open application. The new information will then be reassessed, and a new decision will be provided. 

To request a review please visit the Brighton & Hove City Council website