Sometimes, if you're having trouble with the bot recognizing a specific step, the fastest way to get back on track is to restart the course.
To do this, on a course page, you should see a button at the top that says "Leave course". That should bring up a box, with an un-checked box that says "Do you want to delete your course repository?". Check that box, and then click "Continue and delete (name the repository)". Then, you can re-register. Need help? Start a topic!
This isn't an ideal solution, but if you're ever really feeling stuck, this can be a good way to get things moving again. Good luck, and happy learning!