Rounding of Balance Elements not happening correctly ; Not able to delete/override default (* )round

We are using PDC PS6.

In the tab Balance Elements, For any resource we are trying to add new Event Rounding Rules say , EventBillingProductFeeCycleCycle_forward_monthly

We add its rule with rounding upto 4 precision . The rule flows correctly into BRM and PDC.

However, there is one default rule with Event Name '*'' ,

both * and  EventBillingProductFeeCycleCycle_forward_monthly are for same processing stage "Charging"

While we see in balance impacts the rounding gets applied as per '*' only and not as per the monthly forward event configuration.

We are not able to delete that * configured EventType row from BalanceElments tab, neither it is overridable with any other event.