In the first normal form (1NF), the data should be atomic, and each record/row in the database should be unique.

Atomic data representation means that each cell must contain a single value. In the original data, the actions Password Change and Log On Success both happen at the same time, and all the other fields are the same. Although it feels like it is a backward step, a further record needs to be created to separate out these actions, as follows:

There are now two entries at 09:19:02, but each record only relates to a single event.