Hi Alex, on the Kangertech Protank coil head, you see that it is a chimney-like tube, attached to a cup where the coil is at by a plastic piece. The cup is also the part that screws to the bottom base. Take the chimney in one hand and hold the cup in the other. You should be able to rock back and forth and take the chimney and cup apart. You may need the help of a small set of pliers, but be gentle so you don't dent or crush either piece.
When you have them apart, you'll see the coil itself in the cup. The pieces of silica wick that are *not* threaded through the coil can be taken off. Leave the coil and the silica that is threaded through the coil alone.
Try that. If that doesn't work, you can try a new coil head. Unfortunately, the quality control for those Kangertech Protank heads are not the greatest. So you may experience a difference in quality with them. Later on, if you are inclined to do so, you can actually take apart the coil and build your own. That will give you the best experience with the Protank.
If all this seems like it's not working or you just don't feel like dealing with it, look at the suggestions above and choose a cartomizer
tank and a cartomizer. Although it has a learning curve of its own, there is much less fuss once you've gotten use to starting up a new cartomizer (priming) and filling the cartotank with liquid.