Hello, I’m Nathan, and I’ll be assisting you today.
Sorry to hear that you’re having trouble with this but I’ll do my best to help you out.
The most likely cause of this is that your cartridges were installed incorrectly, or were refilled with the wrong toner.
To start, you'll want to replace the black cartridge at a minimum, preferably with a genuine brother one at least this time: http://amzn.to/2bCTnyj
Let me know if that helps,