Revaluation Activity type in case of Actual price equal to zero

Dear SAP experts,

I'm now working on EHP7 FOR SAP ERP 6.0, SAP NETWEAVER 7.4.

My business scenario is that Actual Value of AT A001 equal to zero because there is no FI posting during period, and there is Actual activity quantity due to confirmation during this period.

When I perform Price calculation  (KSS2 then KSII), system give the result of AT A001 equal to zero at actual price (Price indicator 5)

So the expect result when I perform Revaluation Activity (CON1/CON2) is that the value also equal to zero. But there is no revaluation, the value of Activity type still have value (equal to Plan price x Actual quantity confirmed)

What should I do to have a correct result of revaluation activity in this case?

Thanks for your help

Regards.