creality ender 3 - What's causing my PLA prints to lift like this? - 3D Printing Stack Exchange

I'm printing a Soma cube I found on Thingiverse -- it's a puzzle toy I remember from the early 1970s, and the kind of thing that ought to be really easy-peasy to print. Each of the seven pieces is

creality ender 3 - What's causing my PLA prints to lift like this? - 3D Printing Stack Exchange

creality ender 3 - What's causing my PLA prints to lift like this? - 3D Printing Stack Exchange

How to Change Filament Mid-print Using Cura 4.8 : 11 Steps

Set of 3 Mid Century Modern Print, Set of 3 Colorful Minimalist

Guide to Changing Filament Mid-Print –

Navy Blue Floral Print Skirt - Red Midi Skirt - A-Line Midi Skirt

Anyone know why/how this happens mid print, and any way to fix it?? : r/ender3