Didn't have this issue myself, but in my research it was a common thing - the hand gaurd just isn't centered properly making things look askew. I saw this topic covered on many videos on you tube, you should go there and watch some reviews, some reviewers had to make this same adjustment, it looked very simple to do with a single allen key.
It's a Samson hand guard. Try searching that.
Edit - try this http ://youtu.be/1ClTE3bcr4I
I fixed mine by loosening the six set screws, tighten the bottom pair first and then if it crooked to the left, tighten the right pairs and left pairs last. Reverse the top pairs if crooked to the right. Do not over tighten during this process. Only when everything looks straight, you do the final tightening in the same order. And you might want to check whether the muzzle timed correctly. Mine was off and need fixing.




























