Kanna Treasure Ring should be acquirable multiple times through a restock or repeat of the quest line. This type of game mechanic is already seen with Wings of Fate cape from Mushroom Shrine.
Kanna Treasure Ring is one of five (Reboot) or six (Regular Server) rings that can be starred above 20, and having multiple copies would allow players to more realistically star to 20 or 22 stars without losing a best in slot ring and potentially limiting your character.
Going forward, this would give players a better chance to have more range to keep up with progressively more difficult content.
