Hi, I’ll be glad to help with the printer issue.
Most of the time the color is due to a toner cartridge or drum. If you have replaced them all, then the main issue is that your printer will need a cleaning.
The toner accumulates over time and can color variations in printing. This type of printer will need to be professionally cleaned to get inside and out cleaned very well.
You can try to use a can of compressed air to clean it, but it will need to be taken outside so the toner will not blow around. Next use a damp paper towel with water or Windex and clean all the rollers you can see. Make sure to remove the old toner cartridges and drum unit.
Use a vacuum hose to clean up the loose toner you see around the bottom of the toner cartridge area.