The Remove check box on the AP Void Payments form, Payment Batch grid.

Select this check box for each invoice/transaction you want to remove from the Payment Batch grid. You can also select this check box in the header row to remove all invoices/transactions from the Payment Batch grid.

Once you have finished selecting invoices/transactions to remove, click the Update Batch button. The invoice/transaction is added back to the Eligible To Void grid.