When I host a multiplayer world and my friends join the world, If I hit the home button on my phone it makes my friends leave the world and they can only join back when I go back to Minecraft and when they hit the home button or go over to any other applications (for. ex YouTube) when they come back to Minecraft they are no longer in the world. This issue has been there since version 1.16.210. The game is not being swiped out, It's just being tabbed out while still running in the background but on return it makes you leave the world and you would have to join the world again.