This happened on a friend server, a skygen type (not much importance) and while i was moving my stuff into a shulker, halfway done (trident znd arrow in my inventorry and gears in the shulker)

Then something that happened frequently happened, the server crashed with a common response: Host connection has been lost and then while reconecting, i spawned on the worldspawnpoint, I lost OP permission, my inventory, enderchest, even scoreboard and tag data, luckily i still had my shulker placed with my hears, while we were trying to figure out what happened to me, another crash with same response, when coming back i spawned on my location before the first crash and... inventory back, ender chest, scoreboard and tag too but the shulker with my gear was on my inventory before it was restored so i tought that it had been lost. About 10 mins later i crashed again (same reason) i found myself when relogging with the shulker and once again everything wiped exept the shulker that i had on my with the glitched sessions so i had the idea to place the shulker in my plot (Note that the [name=] selector worked on me) and then i disconected reconected (no crash) and logged back into my normal session. Since i did not encounter that bug again 

Maybe important detail: my friend told me while i was on the giitch sessions that he saw a pc logo next to my name (did not quite get what he said but that meant the game tought i was on pc)

IIF you encounter it i can only advice you to relog until it's fixed