Actual data for QM characteristics of operation 00xx missing

Hi,

We have 3 operation is production order and Inspection characteristic are assigned on operation 0020. When we create production order of quantity- 5 PC. And we are confirming first operation of qty-1/5 and confirm second operation of this same item.

Then its giving the Error message as -Actual data for QM characteristics of operation 0020 missing. this is working fine as per our requirement.

And then i confirm third operation.

When i start confirming 2/5 PC and confirm operation 0010. but when i operation 0020(without maintaining characteristic for this item(serial number), system allowing me to confirm.How to control this as i have not maintained the results for second item-2/5 serial number but maintained only for first serial number item.