Ink Problem with Copier, Fax, Printer Machine

That printer appears to be a Toner Cartridge, as opposed to an Inkjet Cartridge.

Are the sequential black lines at a repeating interval?

If so they may be what is called avalanche in the toner cartridge reman industry.

This is where the drum, or OPC (Organic Photo Conductor) has a wear spot where arcing can occur. Some explanation of the theory behind xerography helps here but it would be long winded. But the long and short of it is the wear spot allows an arc to the PCR (Positive Charge Roller) thereby pulling the power supply voltage below the needed voltage and resulting in a black line across the page.

I'm not familiar with the mita engines but if this happens repeatably the power supply may overheat or go into some sort of failsafe mode resulting in your totally black pages.

I would recommend examining the drum surface for a knick or scratch, you can pull the cartridge out and rotate it to examine it but be sure only to touch the drum near the edges. the drum is normally green, blue, or sometimes a red tint.

Another possibility is that the drum has become "burnt" where extended exposure to sunlight or roomlight will render the organic layer inoperable, but this would not explain the entire black page.

Regardless chances are you need a new toner cartridge, if you have a spare swap it in and see if the problem disappears, if it remains call someone who can repair your printer, it is a more deep seeded issue.

..as well check the cartridge contacts for corrosion or contamination, maybe you just have a bad connection.