Display won't come off
So I am trying to replace the battery on my Motorola X Pure Edition, and right now I have removed 20 screws. The guide I am following shows there are places for 21 screws, on the sim tray slot. Both in the image and on my phone, there is no clear screw in there. Also, when I try to take the display off, I can feel a resistance, is this normal, or did I do something wrong?