Andre Mora

I've experienced this recently (1.17.10) with two ocean explorer maps, purchased from the same cartographer. I entered the monument with the map in hand after I had already raided it once and killed the elder guardians, so it was not the first time I'd explored it. I tried with the maps in the hotbar and offhand.

I eventually got the achievement by purchasing a woodland explorer map from same cartographer and entering the mansion. 

I have experienced this behavior with both tamed cats and wolves in the past week (before the 1.17.11 update) on the Nintendo Switch. I get a "software closed" Switch error. 

The game crashes when I'm in the Nether with the animal and try to return to the Overworld. In all instances I did not intend to bring the animal, so it was not on a lead — they just followed me in. The Nether loaded and worked as expected but once I stepped back into the portal, even if the animal was a few blocks away, the game crashed before the Overworld loaded.

Returning to the Nether and killing the cat solved the problem in one instance.

When I restart the game I'm back in the Overworld, where I assume the game last auto-saved.