All items disappearing after going into nether and leaveing.

i just lost hours of progress logging off in the nether. i took a 2 min clip ill try to upload but when i logged off in the nether on my realm and joined back i had nothing. i could give a guess to why it did this but this bug also happened to another guy on my realm but i thought he was just lieing turns out its a real thing. please PLEASE fix this bug