Why "Months" Recurring is not working without "OnDay" and "OnOrdinalWeek" ?

[pradipbaria]

I see "OnDay" and "OnOrdinalWeek" are optional for "Months" event builder type. But I am getting below exception at OrdinalTargetDay

'Nullable object must have a value.'

[Rishab1988]

There is a private flag which is only updated on using the constructor, with the default false value it can cause an issue it you set the On day property inline via property extender rather than the constructor.