You have the two screws in the forearm cap and the one at the end of the magazine tube. After removing all three, you have to pull the front of the tube down a little over 1/2 inch. Then the tube should come forward, Sometimes it is tough to move down the 1/2 inch because the forearm also have to move down. Sometimes the forearm is a little long and gets wedged between the receiver and the forearm cap tenon. When the is the case, you have to work the forearm down so the tube can move.
You actually see that a lot. Maybe you can sand on it a little so it is not so tight when you put it back together. I know that we are not buying "hand fitted" rifles, but if they have to force it together when building it, maybe they need to look at the issue and fix it.