I have this recurrent problem with underextrusion (printer printing air). I have this with all types of filament of different brands/materials at the start/end/middle of a filament spool. It is simply a random generator. Sometimes the feeder starts slipping immediately, sometimes it takes a few hours, but a print of more than 10 hrs is out of question.
I clean the feeder every time this happens.
I adjusted tension with the screw to middle, maximum, minimum...
I cleaned the bowden tube
Is there anything else i can try?