I wouldn't. If you are mechanically minded you may be able to replace the post, but since it's only been a few weeks, I would probably warranty it honestly. It shouldn't have happened although you may want to check your technique as far as building and compare it to a youtube video or two, to make sure you aren't causing it in some fashion (I am not saying you are, and I'd find it difficult to credit that it would go bad that fast due to user error, but it's possible...
Good luck,
Anna