Amulet of the Nuitari Path

You know Tashas Caustic Brew spell.
Once per day you may cast it without
using a spell slot.
Once a day when you fail a
concentration check on a spell
you may reroll.
When you level up, this spell also gains a level
to a maximum of 3.
If you cast it using a spell slot
the spell is at the same level as the spell slot used.