chunks are missing in the world

I was exploring on my realm and suddenly came across a chunk that looked unloaded. I thought it was a visual glitch, but to my surprise when i looked down the hole there was no bedrock. I decided to try and fly down the hole with my elytra but it would not deploy and it seemed as if i was suffocating in blocks that weren't there. I ended up falling in the void in the over world, with no cheats activated and lost all of my items. Luckily, i just reloaded a backup as i didn't think it was fair that i had lost my valuables to a glitch, but i soon encountered another missing chunk.