At PSA you may that request(which have failed 12th package), if yes then from psa you can load that request data into Excel.
Later you find the releavnt requet which is related to your psa request form cube/dso level.
from target down load that data into excel.
Later use excel sheet options and compare/find the missed records.
Actually when we get delta load failures, first we need to find the error and solve the issue.
later update data. without solving issue why you made req status to green and loaded to further?