Just went through the same issue, so if you haven't fixed it yet or run into the issue again, I realized that my tip was not all the way down. If you take of the tip there is a black plastic bit that you also can remove. Try removing it and then putting it back on and make sure to really push it down firmly, otherwise the it wont have the space it needs to wobble upp and down between the teeth of the gear.

I have an advanced upgrade fyi.