When I look at the episodes, it appears there were two broadcast on the same date. Maybe that is only for subsequent showings, but for example this list shows S1E7 Maru-chan practices cycling Part 1 and S1E8 Maru-chan practices cycling Part 2.

But when I see any collections online, in the File S1E4 both Maru-chan practices cycling Part 1 is followed by Maru-chan practices cycling Part 2. In fact in S1E3, at the end, we hear Maruko say in next week's episode we will have Maru-chan practices cycling. Having the episodes off in TMDB sort of messes up meta data for systems like Plex, that pull episode titles / descriptions from TMDB.