SPEventReceiverStatus.CancelNoError showing error even when it is not supposed to

Question

I am developing GroupUserAdding event receiver in which I am using SPEventReceiverStatus.CancelNoError but it is still throwing error "Sorry, something went wrong" when someone tries to add user in group. It is for SharePoint 2016. Here is my code:

Typing from mobile so formatting may not be there.

public override void GroupUserAdding(SPSecurityEventProperties properties)
{
    base.GroupUserAdding(properties);
base.EventFiringEnabled = false;
properties.Status = SPEventReceiverStatus.CancelNoError;
base EventFiringEnabled = true;
}