I found a titan cursed item that had the condition “break three curses”. I equipped it in Ajax’s second slot. I used Ajax’s first slot as a defence slot for the gate. So technically, the item is equipped. I broke a curse on a titan chest and Ajax’s cursed item still had “break three curses” as the condition. I didn’t know what was needed now to unlock it so rather than problem-solve myself I just unequipped the item and sold it.
You need to uncurse items, not chests.
Maybe the wording needs to be changed then to read “break three ITEM curses” otherwise it’s not clear and it’s confusing!
You Did it right, keeping the item equipped and break 3 other curses, but if on first try, nothing happened then it was a bug. Had same issues before with " Win X Victory Points" and they were bugged, the bar didn’t move at all so spent gems to break them.