Typo perhaps? They released an Errata for the 5E PHB but this was not touched on.
In the Paladin Spell lists (PHB, p. 209), the spell Banishment is listed at 4th level for all Paladins.
On page 88 of the PHB dealing with the Vengeance Oath, one of the three Oath specialties a Paladin can choose, the bonus spell list for level 13 (when you get your first 4th level spell slot) includes Banishment again. Is this redundant, to get from a specialty the same spell that the base class grants to begin with? I'm confused.