Realm restarting

I buy a realm on Nintendo Switch, and when I play on it all work normally, but when we are 5 or more, here start the error, when we hit 5 or mores persons in the realm, 12 or 15 minutes later I try destroy a block and I don’t see the particles, and the persons don’t move, animals too don’t move, 15 or 10 secs later says on screen "Desconection lost” for everyone in the realm, and when I join again the realm restart to the last save, and it restart for everyone, this issue is too on my iPhone realm(IOS) and we don’t have any redstone, commands, or things can cause a crash, and I try close and open the realm and when we hit 5 or more it restart/crash again, any world in the realm, I try restart the realm, but it still crashing, and I try too download the world and play it, and I can lay it normally, please help me fixing this issue the most fast possible yours can, I don’t want lost again my realm days... This issue is too on my realm of iPhone in 1.16.40... Thanks you.