when opening the game and then going into a single player world that was previously generated all achievements had been gained it would reset and only give you achievements like diamond armour achievement if you were wearing diamond armour when entering world and all other achievements were gone.
Comments 3
I just had the same issue in my Server, after being Timed Out, upon rejoining I only had the Diamond Armor Advancement
i can confirm this as an error in 1.14.2. even worse, i broke a diamond hoe just for the advancement that cost me an emerald. i understand its only worth like 5 planks, but still it took a long time to break. also it resets statistics, with the exception of the day your world is on. so mine thinks ive played for 40 minutes on a world thats around day 175
Do you use any data packs?