Minecraft seeds not placeable?

I just played Minecraft and expanded my wheat farm. However, I can hardly plant any more wheat in the expanded field.

In all fields where no wheat is planted, I can't plant it either (in the upper rows there's exactly the same problem, only that I can plant more in the upper rows). Does anyone know why or how to fix it?

You're not the only one, my friend, that happened to me too, probably it's because it's a bug or something

If there's enough light and enough water nearby, it should actually work

Try to make water nearby or a few more torches

Plants need light in Minecraft too.

Is the ceiling open everywhere?

Yes

Do you think it's fixed if I make the ceiling and then put in Glowstone or some other light source because the ceiling is actually open.

Unfortunately I don't know ^^

If you press F3 I think the light level is somewhere

Is it ensured that these blocks are a water block at the same height within 4 blocks?

Also, I would just put Glowstone / Block with torches over the field. The plants need a light level of at least 7