In my experience, Matte PLA + .2 Nozzle = a recipe for disaster.
Which is why I brought that up. At this point, I recommend submitting a ticket to Bambu Lab. I suggest you include this, as they’ll probably be the same things that Malc or I said.
Before you do, these are the last things that could be your issue;
Uno: The extruder gear could be slipping, hence the under-extrusion and random failures.
Dos: The Hotend Assembly could be slightly loose, causing the under-extrusion, or just becoming inconsistent.
Tres: Small defects in the .2 nozzle, such as slightly wet filament, tiny debris, or small calibration errors, which can lead to your issues.
Hope your issue can finally be resolved.
Cheers, 