Based on the answers provided, the following corrections need to be made to the 3D object:

1. Modify the overall shape of the object to be rectangular. Remove any protrusions and indentations that deviate from a simple rectangular form.
2. Add two smaller rectangles connected to the center of the longer edges of the object. Ensure these rectangles are distinct and separate from the main body of the object.
3. Enhance the resemblance to a puzzle piece. This could be achieved by adding more distinct interlocking features that are commonly found in puzzle pieces.