Minecraft Wheat Farm Problem With Water?

As you can see here the water just stops and I don't understand why. Does anyone have an explanation for this?

The water flows into the vacancies. If you want to let water flow over the grain fields I would recommend you to leave the water only on the sides and to build up the open channels so that the incoming water is not caught.

Try filling in the row of blocks where the water stops. In addition, the 1 block wide water flow must not be there.

A bug?

The water in Minecraft makes its way to the next deeper point, just like in reality. So it flows collectively into the middle, because there's a furrow there that is one block deeper.

Simply build the middle furrow with e.g. Steps. Then the water will flow down the field as desired.