One day I logged onto my Minecraft world only to discover my advancements have been reset along with my statistics. This isn't the first time this happened, either. In my previous world.
MC-209383
Advancements and statics reset
Resolved
Duplicate
0
cheri voges
(Unassigned)
Unconfirmed
(Unassigned)
1.16.4
Retrieved
This appears to be a duplicate of MC-187701, which hasn't yet been resolved. If you have any additional information to provide regarding this issue, feel free to comment on the parent ticket. If you feel that this issue is affecting you, feel free to vote for the duplicated ticket, to give Mojang a basic idea of how many people are impacted by the problem. Just to further inform you, this will not determine how quickly the bug gets handled or fixed.