Amber Bateman

Not the OP, but... This issue is still valid.

I log in, waiting almost a full minute for it to fully load the login, and my avatar goes to the correct one instead of a random default, go into my world.
I start searching for wolves to tame.
Tame 5 wolves.
Check the achievements.
Find I can't see them due to having been logged out at some point.
Log back in. Check achievements.
Only 1 wolf was registered as having been tamed.

Happens in all of my worlds, randomly without any warnings, notifications or anything.
Can't get achievements because I can't rely on staying logged in as long as needed.

It seems that the most recent update has caused it to not remember login details for very long, automatically logging me out whenever it times-out. Sometimes on the splash screen, it'll say it's logging me in, claim that I am logged in, before quickly changing to say that I need to log in. So it seems to keep forgetting the details?

Switch version, latest update, single player. Been having multiple issues ever since the aquatic update, when I was unable to log in at all for nearly a year.
Someone really needs to have a proper look at the coding for the switch version, because every new update just seems to cause more problems.

Mostly tooling about in creative now because the survival game is almost unplayable due to sheer number of issues. (stable mobs randomly despawning despite being fine for almost 2 years just being the most recent problem...)
I still get randomly logged out, but at least the achievements being automatically disabled in creative means they aren't affected by it...

Spent a day AFKing at my mob grinder. Healed at least half a dozen zombie villagers. Flipped back to peaceful mode after curing the last villager so I could get them back without any mobs killing them. Got them all back to the base and assigned workstations.
Came back the next day. Did some fishing. Went to check my pets to see which cats I still needed to tame.
All are gone. Cats. Wolves. Sheep with leads. Every last villager, including the sole survivor from the beginning of the playthru.
None were free roaming. All pets were sitting. All villagers were trapped inside houses.
Very annoying, as I had also just finished building a trading post. Not to mention all of the lost resources from healing the villagers. Even the leads vanished.
Haven't checked other villages, as the only one nearby with people is almost a thousand blocks away... I'm too frustrated and shocked at this to bother checking them, and I don't want them to vanish too.
Mobs still spawn though. It seems that only the mobs I actually care about have vanished...

Details:
Platform: Switch (which in itself is buggy af) Using the gamecard, not a downloaded version. Single-player, Peaceful mode. Version: 1.17.40. (I've had several problems since getting this update, this is just the most irritating...)
What was I doing: Building, fishing. No idea when everything vanished. They could have disappeared right after I logged out yesterday for all I know... I only just checked everything after building the trading post.
Travel distance: I didn't leave the base area. So I was near my bed spawn point. Within 100-200 blocks at all times.
Play time: about 2-3 hours on this session. No noticeable lag (for a change. Thought that was sus...)

I'm having this same problem, except on the Switch version. The furnace worked to smelt one single piece or iron ore into an ingot, and then stopped working completely.
Also, weird glitch, but...
I put in multiple ore pieces (24) and coal (8), but when I went back to check on the progress, there was only the 1 ingot. Everything else seems to have been returned to my inventory before I clicked on the furnace?

Just got the latest update, so that's probably the cause?

The Switch version is buggy as hell though. (it didn't let me log in for months. Now I have to respawn and defeat the ender dragon again just to get the original Free the End achievement, because it didn't register the first time...) Every update to it seems to break the game...

Finally been able to log in for literally the first time in months. Took multiple attempts, clearing the log-in data and five minutes of staring at the loading bar...
Kinda annoyed though that the achievements I earned during the entire time that I was unable to log-in haven't been applied. You'd think that there'd be some sort of checks in place to see if you have the requirements and auto-apply them once you get back in, but nope.
So just a heads up: Don't try too hard for them; they won't work until it allows you to log in.

Hey, just adding something that I've noticed fixed my copy (mostly anyway).

I was having no luck logging into minecraft marketplace for months. I couldn't access a brought mash-up pack either.

Due to catching up on missed events in AC:NH, the time on my switch wasn't synced up to the internet. After noticing this, I synced the time to the internet.

The next day, my marketplace suddenly started working again.

I still can't actually log in with my microsoft account, I keep getting errors like creeper, -9 and crossbow... It's possible that redownloading might fix that. I dunno, I'm using a physical copy...

But I can finally access the marketplace, make purchases and downloads. It still goes a bit dodgy if I try to view it too quickly, before it has a chance to load... But I've regained access to the mash-up pack and everything.