The source of the solution is here, my problem was real!
After a firmware upgrade for my HP M281fdw all-in-one printer, it suddenly started complaining about communication problems with one of the supplies. “Supply problem.” on the screen and “The indicated supplies are not communicating correctly with the printer. Try reinstalling the supplies. If the problem persists, replace the supplies to continue printing.” in the help-text. Uncertain about the level of toner in my K container I simply ordered a new one. Of course no one wants to pay ridiculous prices, so I go for the home-brand of 123inkt.nl
Since I knew my CMY had been low for months I decided to change those three at the same time. To my surprise this suddenly gave errors on all four supplies, making me go ‘hmmmm’.
I started googleing and getting more frustrated about my printer not doing what it is supposed to, I remembered I clicked something about a firmware update and forgot about it. Then I found this article which gave me the option to downgrade… AND IT WORKED! My toner was actually still at 90%
So, HP, Hewlett Packard, you F@!^%#$-ing B@#&$%ards, blocking non-HP toners is so stupid, low-blowing and unbelievable, I am thinking about calling my lawyer to see if that is even legal, blocking me to use the more enonomical printer-supplies-brand I prefer and costing me a day of waiting for a newly ordered toner and a couple of hours of aggravation before I could solve this issue with finally a firmware downgrade.
Anyway, below the solution, which I copied from the other website: