Their web application isn't the canonical source of whether they owe you money or not, a court decides that. I don't know in which jurisdiction Freelancer are based, but if there is a low cost small claims procedure, sounds like that would be worth you time.
In the UK in a variety of circumstances you can petition a court to issue a wind up ("liquidation") order for a company if it refuses to service its debt to you.
In the UK in a variety of circumstances you can petition a court to issue a wind up ("liquidation") order for a company if it refuses to service its debt to you.