poofy_cat
It might just be the specific spool/brand of PETG you used. Try buying some from a major well-known manufacturer, like Overture, Polymaker, etc. I’ve had cheaper brands shrink, warp, have adhesion issues, and all sorts of other quirks.
I had one weird roll of PETG that could only be printed at lower temperatures, so it’s possible. Still looks like the filament is wet to me… I recommend picking up a Sunlu S1 Plus when it drops under $40, I like being able to both dry the spool and print straight from the dryer (only takes a couple hours to re-absorb moisture).
This model was set up for it already in the .3mf file. It stops, moves the toolhead over, automatically unloads the filament, and waits for me to yank it the rest of the way out then stick in another color. It then purges the nozzle a bit to get the main color fully flowing and asks you if it’s correct before proceeding. I did this like 7 times for this stupid half-failed box lol.
Edit: Also, you can left-click the plus sign on the layer slider at any height you want after slicing in PrusaSlicer to add manual color changes in.