If you think there is a problem at a coop the first step is check what the cooperative by-law says about the matter.
You should then talk to the coop or if your concern is serious you should put it in writing. When you do either of these:

• Be clear about what the problem is
• Explain what you want the cooperative to do
• Ask for a response within a reasonable time
• Be polite
• Keep a record—what happened, the date and the name of the person you spoke to, or a copy of any letters or emails you sent.

If you aren't happy with the coop's response you should consider lodging a formal complaint about the matter with the Registrar's office.