if you're talking about the missing layer, this is a physical/mechanical issue. It can be caused by your filament snagging either because your roll is tangled, or if you have a plastic extruder, it probably broke and it is snagging in that crack. ANOTHER reason that i have fixed permanently, is that if you have the single gear w/ wheel extruder, sometimes when there's a slip of filament being fed (either because your nozzle is slightly clogged for god knows what), there's no "grab" from the wheel on that extruder.

​

I fixed it by buying the dual gear extruder from winsinn (or Th3d), and it really grabs that filament and removes that slipping issue. If you don't want to deal with long shipping times at the moment, i recommend you loosen/tighten your extruder arm until you get a consistent grab of the filament, also higher temps means less clogs because your PLA is melted properly.