We are trying to reterive data from the _SMSMessageTracking data view in order to populate another DE with undelivered and delivered statuses.
We've found there is a difference between Undelivered and Delivered fields - i.e. they are not always populated with the opposite values. In addition, there are records where Undelivered is null whereas Delivered = 1.
We did not find any explanation on the documentation for the differences observed above. Could anyone clear this up why is the difference?