is there a tension adjustment for the belt? If so, then perhaps you need to tighten it. If not, then you may have a defective spindle (too small,not “true”,etc). You may need to replace that.
You also might want to look on Amazon.com and see what reviewers say about that model. While some of the reviews are useless, many times I have found that user detect problems common to certain models.
Like someone else said, if you are still under warranty which you seem to be, then I’d have them troubleshoot and fix the problem for you.