If you're trying to jump onto that leafy/boney bar thing that's elevated that you need to use a raptor to jump up on, you need to stand back a bit with the character (not too far, but not too close), and hold down the button until a reticle appears, and aim that at the bar. Upon releasing, the raptor should jump up.

He jumps, you're upstairs and then you face an invisible wall.

You will face this bug several times in the game, many players moan about it.
However, the solution is (mostly) pretty easy, because the reason of that bug is kinda stupid.

You can stop the game from glitching by simply:
1) Turn on V-Sync. This should help. If it does not:
2) Change your screen resolution to 1920x1080.

Then keep on gaming! :)
If you faced the problem and found another solution, feel free to tell us in the comments.

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