video has to be shot with camera tracking in mind because not all shops will work. You need a sufficient amount of fixed geometry that has a sufficient amount of detail in a shot for camera tracking to work. For example, if you are walking down a very crowded sidewalk filled with hundreds and hundreds of people and shooting with your cell phone while you're walking the shot will not track properly. Even if tracking works there so much moving in the frame that there is nothing to get a solution prom. If you are standing on the beach and there's a big blue sky and your panning around on the surf rolling in that shot will not work either.
If you think there is enough detail in your shot you can try trimming the shot so it's not as long. If that does not work a completely accurate description of the shot or better yet posting the shot so we can see it will help us point you toward a solution.