INScancount method override

Hi  Team,

We would like to override below base method (ConfirmRow()) from INScancount graph (Scan and Count ) ,we have tried below but its not working, Can you please advise how can we achieve this,

[PXOverride]
        public class ConfirmLogicExt : ScanExtension<CountMode.ConfirmState.Logic>
        {
            public static bool IsActive() { return true; }
            public string Prompt => Basis.Localize(Msg.Prompt, Basis.SightOf<WMSScanHeader.inventoryID>(), Basis.Qty, Basis.UOM);
            public CountMode.ConfirmState.Logic Mode { get; private set; }
            protected FlowStatus PerformConfirmation() => Basis.Get<Logic>().Confirm();


            public class Logic : ScanExtension
            {
                protected  Func<FlowStatus> var1;
                public static bool IsActive() { return true; }
                public virtual FlowStatus Confirm()
                {

                    if (!CanConfirm(out var error))
                        return error;

                    return ConfirmRow(var1);
                }
                //[PXOverride]
                protected virtual FlowStatus ConfirmRow(Func<FlowStatus> base_ProcessAdd)
                {
}
}
}