They are third-party lenses. They use reverse-engineered firmware that can cause the AF to stop working if Nikon add new functionality to the communications protocol.
At this price point, there is probably very little quality control applied. This means large sample variation as every item produced reaches the consumer.
What you pay for with a Nikkor is consistency because of tighter tolerances in production and a better QC protocol, often a more complex shape to the aperture blades giving a rounder opening, higher quality glass and coatings and a distribution network that stand behind their products.
The better, more established third-party manufacturers are at the same level as the camera manufacturers these days, but the same canĀ“t be said about many of the newcomers who use a low price to attract customers.