How quantity canceled field updated after the confirm shipment or R42750

Dear Support,

For sample order with zero price(added thru price history), F42199 shows the line is ship confirmed, on hand updated but still in next row it shows the quantity cancel =1 (by program R42750) but the line has the correct status 560-580, no cancel date ( every thing is fine at F4111). here is the screeenshot.

I only want to know how the quantity canceled field updated to 1 by reprice job ( further it is not allowing to sales update too).

Thanks for your support.

Thanks,

Subodh