I'm not one hundred percent familiar with the model you have, but the problem is not an unusual one, especially if you have a hot end which uses a bowden tube of any length inside the heat sink. If you have a bowden tube, push the release fitting and pull it out while the nozzle is at the right temperature for your filament. You'll want to ensure that the cavity is clear of filament and re-insert the bowden tube until it bottoms out. Perhaps if you can, replace the tube, or cut it back to remove the "teeth marks" left by the release fitting.

If the tube is not pushed all the way in, the blob will form on a regular basis and may eventually jam without a filament swap. Another thing to consider is when you are removing the filament, extrude a few millimeters before you retract, which of course requires that the nozzle be at the correct temperature.

Even direct drive systems have a bit of PTFE tube, so ensure that yours is fully inserted. Use a toothpick or similar item to locate the depth at which the throat changes diameter and match it to the amount of PTFE tube that is inserted.