Try this. Remove semicolon for Then
in If
WhilePrintingRecords;
EvaluateAfter({@Share_Hundred_Percent});
EvaluateAfter({@Less_Commission});
EvaluateAfter({@Payment_NICL});
EvaluateAfter({@Payment_PRCL});
Shared numberVar sumNetPayable;
numberVar result;
if({Command.GENCLIENTCODE}=990) then
result:= {@Share_Hundred_Percent} - {@Less_Commission} + {@Payment_PRCL}
else
result:= {@Share_Hundred_Percent} - {@Less_Commission};
sumNetPayable := sumNetPayable + result;
result