Update Scheduled Bill Payment

Update Scheduled Bill Payment. This endpoint allows the scheduled bill payment to be updated, using the paymentIdentifier.
• A one-time Bill Pay schedule cannot be changed to a recurring schedule by changing the frequencyType, because one time and recurring bill pay are under different model schema.
• To change Bill Pay schedules, the customer must delete the one-time bill Pay schedule and create a new recurring bill Pay schedule.
• The frequencyType for recurring bill Pay schedules cannot be changed to oneTime or the frequencyType that was previously set for the bill Pay schedule.
• The frequencyType of 'oneTime' cannot be updated to another frequencyType. Recurring frequencyType can be updated to another recurring frequencyType (i.e. weekly or every2weeks, etc.), except oneTime.