So I have a world (NOT A REALM WORLD, A LOCAL ONE) with a friend I make and I back it up on a regular basis should we need to revert changes or serve as an emergency save in case the world ever got corrupted. However, within the past few days, I keep receiving the same issue where I would attempt to export the world, opening up the file prompt of where I wish to save the said backup, but not notifying me that it was backing up. When I tried to do it again it shows me that it does save the world and file type, but with no data (0 KB) saved onto it.

I've tried several things, including updating the game, copying the world within the game itself, and looking for online suggestions, yet the problem still persists. Is it something I'm doing wrong or is it Minecraft itself?