What can DPBR to proceed

I own a unit in a 25 apartmen building that is a cooperative, not for profit corporation,since 1957. The board is praticing selective enforcement, while they brake the rules?
I checked with DPBR and they cant find us registered? And according to the law they should register with them if they are a cooperative.

Adriana - does this describe your co-op setup?

From WiseGeek;

A Co-op or a housing cooperative is a unit in generally a large building that is leased exclusively to the person who purchases it. Buying a co-op apartment is different than buying a house. Instead of actually buying the property where you live, what you are doing is buying into a corporation, usually a limited liability corporation (LLC) that owns the building. Once you purchase these shares, you have an apartment that you and family get to live in, but renting that apartment out, or doing anything illegal in the eyes of the corporation (like having too many occupants) can land you in trouble.

Your co-op apartment, and every other apartment in a building, is subject to the bylaws the corporations establishes, provided these aren’t in conflict with state law. The board can have deciding power over whether or not you can buy a co-op apartment, and may also have the power to deny or approve your right to rent that apartment. They can often turn down any tenants you wish to sublet your apartment to, if their tenancy would somehow conflict with co-op rules, and some co-op boards can be fairly picky and deny without cause your proposed rental of the apartment to any tenants they deem unsuitable. The board also must approve any person to whom you wish to sell your co-op. . . .

So you can see that there IS a corporation, run by a board.