We play on an Xbox One X, usually local play with 2-3 players, and this has happened to us a handful of times in the last week.
The first instance was immediately after completing the secret cow level (as a 3, in local play). After we finished the level, I also purchased the Hero pack DLC and installed it.
Restarting the game later found at least two of us had lost significant enchantment points (they went into the negative), lost a meaningful number of levels (one dropped from the 90s to low 80s), and lost items. Some items were duplicated, and while some enchantment points could be recovered by selling duplicates, there was absolutely a net loss in points, levels and items.
This happened again twice more, having played and completed the secret level (including after a single player game, so it was not restricted to co-op play), so we've decided not to play that level any more, which is very frustrating.
So far, the DLC has not caused this issue (we've played 2 of the 3 new levels).
So this happened again, and again it rolled back one user by over 14 levels and put the enchantments to negative 40. This game is unplayable in its current state.
Given that this only started once I downloaded the DLC, I assume it's something to do with that, but in any case I'll be requesting a refund from Microsoft, as this is absolutely unplayable with a problem of this magnitude, and the fact that it hasn't been addressed yet is really not good enough.
If the Xbox allowed you to copy save files, you could possibly mitigate against this somewhat, but as it stands the game is basically ruined because of this issue. Playing on an Xbox One X, in local co-op with 2 or 3 people, while playing the new DLC levels. The issue hasn't happened during single player games (yet).
I've dropped a couple of screenshots showing the negative enchantment points that occur when this error happens, and how the items worn are sometime duplicated in the inventory.
The issue of duplicating inventory and lost enchantment points is frustrating, but nowhere near as bad as the fact that character progression is rolled back, and items since that rollback level are lost. This is what makes the game unplayable with this bug in play.
Honestly, it's astonishing that this problem still exists, and that nobody at Mojang has been able to provide any kind of update.
We play on an Xbox One X, usually local play with 2-3 players, and this has happened to us a handful of times in the last week.
The first instance was immediately after completing the secret cow level (as a 3, in local play). After we finished the level, I also purchased the Hero pack DLC and installed it.
Restarting the game later found at least two of us had lost significant enchantment points (they went into the negative), lost a meaningful number of levels (one dropped from the 90s to low 80s), and lost items. Some items were duplicated, and while some enchantment points could be recovered by selling duplicates, there was absolutely a net loss in points, levels and items.
This happened again twice more, having played and completed the secret level (including after a single player game, so it was not restricted to co-op play), so we've decided not to play that level any more, which is very frustrating.
So far, the DLC has not caused this issue (we've played 2 of the 3 new levels).
So this happened again, and again it rolled back one user by over 14 levels and put the enchantments to negative 40. This game is unplayable in its current state.
Given that this only started once I downloaded the DLC, I assume it's something to do with that, but in any case I'll be requesting a refund from Microsoft, as this is absolutely unplayable with a problem of this magnitude, and the fact that it hasn't been addressed yet is really not good enough.
If the Xbox allowed you to copy save files, you could possibly mitigate against this somewhat, but as it stands the game is basically ruined because of this issue. Playing on an Xbox One X, in local co-op with 2 or 3 people, while playing the new DLC levels. The issue hasn't happened during single player games (yet).
I've dropped a couple of screenshots showing the negative enchantment points that occur when this error happens, and how the items worn are sometime duplicated in the inventory.
The issue of duplicating inventory and lost enchantment points is frustrating, but nowhere near as bad as the fact that character progression is rolled back, and items since that rollback level are lost. This is what makes the game unplayable with this bug in play.
Honestly, it's astonishing that this problem still exists, and that nobody at Mojang has been able to provide any kind of update.
FYI - this is during local co-op on Xbox One X
9 months and no acknowledgement, let alone resolution, is really not good enough. This is a game-breaking bug. Please fix it.