The upside-down information was really important as it highlights the classic Bambu PETG default setting issues. They are quite well documented in the forum. For example here: [SOLVED] PETG problem on large support surface
The bad side was not by any chance facing the fan?
The easy fix is to reduce speed and/or adaptive layer height. There’s also a bit of tweaking of the cooling fans that you could do. The easiest approach in setting up is to use the Generic PETG settings instead of the Bambu PETG settings.
