3818290 - Why does an exception message show %lines% instead of the report ID where duplicate transaction is existing?

I can see duplicate transaction exception message is triggered on a report. However, it doesn't show the details of the report where the duplicate transaction can be found. Instead, it only shows %lines%. Why is it like this?

When duplicate check is triggered, it only shows %lines% instead of the details of the report where the duplicate transaction is present , KBA , CON-EXP-EXP , Expenses , CON-EXP-ADM-AUR , Audit Rules , Problem