If the plate will not rotate out and the bin that holds discs is in place on the plate, the bin has been placed on the plate improperly. Gently remove the plastic bin off the plate and out of the unit. Then press the rotation button at the top of the unit, next to the display screen. The plate should then rotate out.
Ensure that the bin is being placed on the plate properly. There is a handle on the bin that can be gripped by your thumb and index finger and should be facing you when placed on the plate, when the plate is out. The plate will then be able to rotate freely.