Creating a Breakout Game for Beginners: ball falling through paddle

Following the learn unit mentioned above, the ball seems to be falling through the paddle,(24:30 mark), paddle has both rigidbody(with bouncy), and a box collider, but the ball falls through. What am I missing?

If the ball is going too fast, Unity may not be able to recognize the collider. Try this:
In the Rigidbody component set “Collision Detection” to “Continuous dynamic”. This has fixed my problem with rigidbody bullets going too fast.