My son plays minecraft PE in creative and recently he played a few times in survival.
Today to his dismay (and mine - as it involved desperate screaming) a few of his buildings suddenly disappeared into something that looks like the sky.
There are still a few elements and some animals visible but they are all unreachable.
It seems like his world was suddenly cut into a smaller square than it originally was and all the buildings and stuff that were outside this border are corrupted and not reachable.
Anybody knows what the problem can be and how to fix it?
Please help
Thanks in advance!