I once had massive nozzle issues. Filament would stop extruding at random points, strange shell and roof textures, etc. Cleaned out the extruder multiple times. Same problem on both nozzles. Even replaced a heater. No luck.

Turns out it was a batch of poor quality filament. Switched brands, never had an issue since.

Filament ages, it absorbs moisture, it dries out, it can have impurities, it can have airpockets, it can be something other than what it says on the box... get yourself some samples from a different supplier and try that. My opinion.