This might be a problem with saving things, but sometimes when I join my (or other’s) condo some data is “switched” around. This could be canvas or laser projector settings. This can be fixed with reloading.
All the images haven’t been swapped, but it just uses the data from other canvas as the original canvas that these images were copied from are still what they’re meant to be.
This also happens with things like plushies where the colour just goes to white.
I had this problem when I copied and pasted a snapshot of another account to a different account.
Not sure if the snapshot was originally corrupted or not, but by using “current condo snapshot” I was able to restore it.
If you didn’t do this, it’s most likely another snapshot bug.
Even without swapping them between accounts, TU snapshots are very unreliable (I’ve had them being corrupted multiple times in the past) even on low item counts.
Never trust them at all and save into multiple snapshots and make separate backups.