I reverted all the subschemas in my test payroll schemas and my test wagetype is still with '6' and now it seems both the tables DDNTK and ARRRS are updated with the values of the amount that cannot be deducted.
But the error as described above still occurs, specifically in the 2nd loop. From the message it seems like the system is still trying to deduct something even though the net amount is 0! I expect it to do only 1 loop (since the net amount is 0).
I then tried with specification '3' and the error still happens at the execution of function PRPRI in the 2nd loop.