Flat world "/fill" bug

For some reason, ever since the first 1.20 hot fix, the command "/fill" on flat worlds is just completely bugged out. I've tried different ways. One of them including "/fill 20 -59 20 120 -59 120 gold_block". It doesn't give a syntax or block limit error, it just keeps saying " Cannot place blocks outside of the world". I've tried this at different levels. Y=-59  Y=0  Y=20 and even different X and Z levels, no matter what I've done, it just keeps bringing it up, even if I do the replace command. What in the netherspawn is going on here!?