Answer:
dirty fuser roller
Explanation:
The most likely cause for this issue would be a dirty fuser roller. This is a device commonly found on laser printers. When this part of the printer is dirty it tends either to leave the dirt on the page or make very tiny indents on the page when the roller passes over it. Both of these scenarios prevent the ink from properly adhering to the paper or even passes over that specific section which ultimately leads to black or empty spots.
