Hi HappyM,
Welcome to the HP Forums, I hope you enjoy your experience!
I understand the black isn't printing properly.
I will be happy to help you.
Here is document for the black not printing correctly to see if we can resolve this issue.
Printer Does Not Print Black Ink or Color Ink, or Prints Blank Pages.
I have provided a document to clean the contacts on the cartridges.
'Ink Cartridge Problem,' 'Incompatible Ink Cartridge,' or 'Ink Cartridge Failure' Message Displays on the Control Panel. Disregard the title.
This document will provide instructions for manually cleaning the printhead.
'Missing or Failed Printhead' or 'Printhead is Missing, Not Detected, or Not Properly Installed' Message Displays on the Control Panel. Disregard the title.
Are you using Genuine HP Cartridges?
What are the ink levels?
Hope this helps.
Thank you for posting on the HP Forums.
Have a nice day!