Constant jamming

[StarShadow 0]

So recently I have been having problems with jamming, and it actually got to a point where it was so bad, that I couldn't fix it easily.

I took apart the entire hotend, did an atomic pull while holding the heater block with some pliers, and cleaned the nozzle with acetone. Now that it was clean again, I reassembled it, and it still hardly comes out, and jams.

The temperature of the nozzle is not the issue, but when the filament is pushed into the nozzle it doesn't want to come out.

One thing that I have noticed from when I was cleaning it, is that when filament is pushed into the nozzle, rather than actually extruding, it just melts and goes back onto itself. Even when the nozzle is completely clear, the filament would rather build up inside the nozzle and up into the metal piece under the isolator.

Does anyone know why this happens, the filament is melting perfectly at the recommended temperature of 210C but doesn't extrude out of a Clean nozzle. I've cleaned it so many times I just don't know what to do.