where to post advocate fee in cooperative society,

Are you going to wait till the accused pays it?  I think not. If you present your bill they have to pay you right away and show it as expenditure. If they hope to receive the amount from the "accused", they should also show the amount as "amount receivable" on the assets side of the balance sheet. In due course if they find that the amount is not recoverable, they should write it off with the approval of the General Body.