Changed quality - previously outstanding, now very poor

I buy for 20 years Original toner because I value quality and have now bought packs a lot of money for two of these Original HP, as always. I have spots on the paper, streaks, gray shadows, the writing is gray instead of black, two-sided printing is not, then everything is only provided with gray streaks. Either I caught a Monday cartridge, or the quality is at the same high price has become very bad. This will turn out in the next through my high consumption very soon. Should the repeat so, I will complain and the toner will soon use an alternate product which then only costs a fraction and definitely can not be worse than this.